Sections

Services

Information

UK United Kingdom

Why energy-saving homes often use more energy

Energy efficient houses are often thought to be a promising way to reduce our environmental footprint by using less energy and producing fewer greenhouse gas emissions. Yet, surprisingly, if you consider…

New homes go up at a housing estate at Cecil Hills in western Sydney. AAP/Dean Lewins

Energy efficient houses are often thought to be a promising way to reduce our environmental footprint by using less energy and producing fewer greenhouse gas emissions. Yet, surprisingly, if you consider the whole life cycle of a house, it turns out that sometimes a new home designed to save energy can end up using more than an average house.

Our study, published in the December edition of the journal Applied Energy, found that current building regulations are failing to adequately address the broad scope of energy use associated with buildings. We need to start thinking about building materials, size, location and lifestyles - not just heating and cooling.

Rating Australian homes

In Australia, the star-rating scheme measures the energy efficiency of residential buildings on a scale of 1 to 10 stars, with 10 being extremely energy efficient and requiring very little energy for heating and cooling.

The higher the star-rating, the more materials are typically required - such as for insulation, glazing, efficient window frames - in order to reduce heating and cooling energy demand. All these materials require energy to produce, known as their embodied energy.

In a climate such as Melbourne’s, a 6-star rated home would require 114 megajoules of energy per square metre each year for heating and cooling, which works out to be 27,360 megajoules a year for a typical new 240m² house. That’s two-thirds less energy for heating and cooling than an average Melbourne home.

If you go even further and achieve an 8-star rating, that falls to 54 megajoules per square metre - or 12,960 megajoules a year for a 240m² house. That’s a good enough result to earn a “passive house” certification in Europe.

However, we found that the additional embodied energy of the materials needed to achieve this improved performance would equate to at least 500,000 to 800,000 megajoules of energy for a new 240m² house, even before you moved in. That’s equivalent to the energy you would need to heat and cool the home for 15 to 25 years.

Counting more than energy bills

A house is not just a space to heat or cool: it’s an organised assembly of numerous materials to produce indoor and outdoor spaces. Within these spaces, thermal comfort is required and energy is used to maintain it. Energy is also needed for lighting, appliances, cooking and hot water.

At a larger scale, buildings form neighbourhoods, which in turn form cities. The type and layout of those buildings greatly influence travel distances and the associated energy needed for transport.

Most new houses are built in the outer suburbs of our major cities, often with a lack of reliable public transport services, forcing householders to rely on cars for travelling long distances. This leads to a significant demand for transport-related energy, particularly petrol, especially compared to inner-city households.

The total operational, embodied and transport energy associated with a super insulated house near Brussels, Belgium (equivalent to an 8 to 9-star house in Australia) was compared to the same house built to minimum requirements (6-star equivalent) and an apartment in the city (5-star equivalent).

Four and two occupants were assumed to live in each of the houses and the city apartment, respectively. The occupants of both houses in the suburbs rely on cars for their mobility, while those in the city travel by trams, trains and car.

Figure 1 compares the total energy use of the three buildings over 50 years, per person.

Figure 1: Total energy demand over 50 years for suburban low-energy and standard houses and a city apartment in Brussels, Belgium, by use

As can be seen above, the total energy use of the passive house (8 to 9-star equivalent) is only marginally less than that of the standard house, and 1.7 times higher than the city apartment.

A closer look shows that the low-energy house requires much more embodied energy than a standard house because of the additional insulation and triple glazed windows it uses. So even though the low-energy house has much lower energy bills for heating (and cooling), that’s offset by a similar increase in embodied energy, negating any benefits offered by the additional materials.

The city apartment results in lower energy use across all categories. This is due to the smaller living space per person, meaning fewer materials and a smaller area to heat and cool. Also, the increased use of public transport greatly reduces transport-related energy demand.

The bigger picture

With all three of our case study homes, more than 50% of the energy demand associated with the house is the embodied energy and energy for transport. What this highlights is that our current energy efficiency schemes and regulations are failing to comprehensively address the broad range of energy demands for building and living in our homes and cities.

In fact, the space heating and cooling demand - which is the focus of most regulations and schemes - represents merely 3%, 9% and 29% of the total energy use for the low-energy house, the standard house and city apartment, respectively.

The current preoccupation with improving energy efficiency for heating and cooling means that the significant indirect energy requirements of houses are often overlooked. This is why we need more comprehensive regulations and schemes that take into account other factors, including house size, the materials used within them, and where they are located.

Trying to reduce our heating and cooling bills is a good start. But there is even greater potential to save energy by considering the materials used to build our homes and the way we move around. Now is the time to look beyond individual homes, and start building better, more affordable, more energy-efficient neighbourhoods and cities.

Join the conversation

119 Comments sorted by

  1. Alex Cannara

    logged in via LinkedIn

    Very good. And, here in the US, we have even more absurd errors in what;s 'green' housing.

    One of the most egregious is the tendency to ignore the immediate environment. For example, a home's sunlit roof generates over 50kW of waste heat directly into the environment This is down-conversion of visible light to IR, which then re-radiates upward to excite GHGs.

    If the house roof were reflective, or shaded by trees, this would not occur. The Calif. Energy Comm. and the LBL Heat Island Group…

    Read more
    1. Steve Hindle

      logged in via email @bigpond.com

      In reply to Alex Cannara

      An interesting point, I have felt a similar effect with vehicle paint. A friend had the roof of his car sprayed with an expensive heat reflective paint. Even though it looked identical to the paint elsewhere on the car, it was far cooler when touched. Presumably he saved on fuel with less air conditioning.

      report
  2. John Kerr

    IT Education

    It is great to see that someone is looking at the overall picture rather than just the myopic energy use costs. If an energy efficient house costs twice as much to build then the real cost of its energy use is much higher than just the heating and cooling.

    We need to do more of this sort of analysis in all areas. We seem to be obsessed with just the cost of producing things without consideration of the 'other' costs. For example, the cost of coal produced seems to be based on actual extraction…

    Read more
    1. Mike Stasse

      Retired Energy Consultant

      In reply to John Kerr

      There is ABSOLUTELY no reason for an energy efficient house to cost more than a conventional one.

      Windows are the most expensive part of a building envelope, and it's windows (siting and size) that almost always cause efficiency problems..... glass facing E & W, or glazing that is way too large.

      The building/architectural industry have this stupid mantra of "introducing the environment inside your house" which I call camping. Outside temperatures can vary dramatically seasonally, and even…

      Read more
  3. Tony Bryer
    Tony Bryer is a Friend of The Conversation.

    Software developer

    Are city apartments (I live in one) more energy efficient? A 2007 report (whose findings may now be out of date) reported that "Average emissions per occupant in high rise apartments are twice as high as in detached homes." [Melbourne Age story, "Making a farce of five-star", May 21, 2007].

    This may seem counter-intuitive, but the explanation is the large amount of energy used in lighting common parts. In my building 40 floors of corridor, a large foyer and a 500-space car park are lit 24/7. We're looking at swapping to LED lighting but deciding whether to do it now or to wait for the cost to fall further is a hard call.

    report
  4. John Newlands

    tree changer

    I recall a TV interview with the owner of a Sydney home that had PV, water recycling and a vegie garden where they insisted the home was 'sustainable'. Apart from the energy that went into making bricks, glass etc it also ignored the SUV in the driveway, the large LPG cylinder and the fact the garden basically produced a few lettuces.

    I wonder how well a passivhaus designed to European specifications would cope with our 45C heat. Rather than standards for new homes we should consider ways to make existing homes more energy efficient, pink batts scheme aside. With an ageing population in ageing houses this problem will get serious.

    report
    1. Chris O'Neill

      Retired Way Before 70

      In reply to John Newlands

      "I wonder how well a passivhaus designed to European specifications would cope with our 45C heat."

      I would expect that as long as external window shading is added as necessary, they should cope pretty well. Hey, an awful lot of Australian houses don't even have that!

      report
    1. David Arthur

      resistance gnome

      In reply to John Barker

      "low food mile food" - the houses in the suburbs could be surrounded with vegetable gardens and a chook pen - I don't know how this could be factored into the star-ratng system, or even whether it should be.

      report
    2. David Arthur

      resistance gnome

      In reply to John Barker

      "I have suggested- to the furor of some- that dollar values are probably a good proxy for following detailed energy trails- if it costs less then it probably takes less energy."

      We could make this proposal more appropriate by modifying the GST on fossil fuels from "10% of price" to "10% of price PLUS $X per tonne contained carbon for those goods that are coal, petroleum or 'natural' gas (incl shale gas and CSG".

      Then all we do is increase X each year until the transition away from fossil fuel use to the extent required is achieved.

      report
    3. David Bindoff

      manager

      In reply to John Barker

      pv panels have a long history and (I think) strong methodology for lifecycle ghg and other emissions eroi etc. look up Alsema and Fthenakis and if you know of problems tell us what they are please. Wind also is well understood afaik. Nuclear is cloaked in secrecy, I've never found anything decent.

      report
  5. Stephen Ralph

    carer at n/a

    perhaps the overall picture should consider non-energy using factors to heat and cool houses.
    Double or triple-glazing, better insulation, making better use of breezes/winds to cool houses - which means design improvement, less emphasis on huge open spaces, better use of trees or shrubs to protect windows etc - quite difficult these days as houses take up to 95% of land space.

    report
  6. Ryan Farquharson

    Research Officer

    Great work.

    As someone looking to build in the next few years it's really difficult to find this sort of information. There are a few 'zero carbon' homes around where the embodied energy is taken into account, but these come at an even greater $ premium than the 7-8 star homes, which are at a premium again over the 6 star homes.

    The Your Home technical manual http://www.yourhome.gov.au/technical/index.html provides some basic information, but not the technical detail one needs to make informed…

    Read more
  7. Jeremy Dawson
    Jeremy Dawson is a Friend of The Conversation.

    researcher

    The authors say "This is why we need more comprehensive regulations and schemes that take into account other factors, including house size, the materials used within them, and where they are located."

    The preference for ever more detailed regulation is very much a political value judgement of the authors. Others would say we need to increase the cost/taxation of energy use, which would provide a disincentive to energy use which applies equally to all categories - embodied, heating/cooling, transport, or anything else that the researchers haven't discovered and measured yet. It doesn't take an army of bureaucrats devising more and better regulation.

    report
    1. Felix MacNeill

      Environmental Manager

      In reply to Jeremy Dawson

      Jeremy, if you combined this kind of idea - essentially making people pay for externalities - with John Baker's useful rough heuristic that more cost equals more emissions, you would start to have something that really did add up reliably and would require no further regulation or bureaucracy.

      I wrestle with these kinds of issues with commercial/office buildings: untouched versus refurbished versus new build...the further you go through that sequence, the lower the energy intensity to operate…

      Read more
  8. Paul Prociv

    ex medical academic; botanical engineer at University of Queensland

    Thanks for a thoughtful and timely analysis. Any chance of another one, incorporating a consideration of the energy benefits (or not) of photovoltaic power and solar hot water systems, please?

    report
    1. Michael Shand

      Software Tester

      In reply to Paul Prociv

      And Coal for that matter

      You gotta compare it to something right? rather than just say, Ohhh how terrible, solar panels require energy to produce....best keep digging up and transporting coal then.....say what?

      report
    2. Paul Felix

      Builder

      In reply to Paul Prociv

      I have installed 25+kwatts of solar panels, I cannot comment of the actual cost vs actual benefit, but I do have an observation.
      In Tas we have a guaranteed 28c kw payment, variable if prices rises or falls, until 2019.
      That means, if you are wealthy, you can stick a 10 kw system on your house approx $14000. You increase the capital value of your home and if you are careful in your use you can cover your total energy bill and get a reimbursement in dollars.
      This means that Aurora pays you significantly more than is costs them to produce.
      The consequence is that if you are rich you can make money but if you are poor you have to subsidize the power costs of those who can afford to put in solar hw and panels.
      My position is that it would be better to have solar farms were the benefits could be used to help low income people get cheaper power.

      report
  9. Ivan Quail

    maverick

    Thanks for a very interesting article.
    It highlights the need for more compact suburban living with better public transport services and separate cycle ways to local shops. Roads were designed for cars and buses not cyclists.
    The embodied energy of fired bricks and concrete is huge. I am disappointed that green concrete is not more widely used for both.
    A good point from Alex Cannara that roofs and walls should be much more reflective and of course building orientation is also important.

    report
  10. Rachel Dawson

    ecologist

    It seems to me that minimizing energy use really gets back to common sense. Eliminating the most wasteful practices would be a good start. For example politicians traveling around in chartered jets, city skyscrapers cooled to 18 degrees permanently during summer, restaurant goers sitting al fresco on chilly evenings heated with outdoor gas burners, decent houses being demolished to make way for new 3 garage ones......the list goes on.
    I was struck by the absurdity of the insulation scheme when…

    Read more
  11. Michael Shand

    Software Tester

    This is an old and lame argument

    Becuase you need to burn coal to produce a wind turbine

    It is better not to build a wind turbine

    OR

    Because you need to fly A1 Jet Fuel to have international climate discussions

    You shouldn't have climate discussions

    Lame, uninteresting, unoriginal, weak sauce

    report
    1. Andrew Gilmour

      logged in via Facebook

      In reply to Michael Shand

      This is and oldie but goodie.

      Very often green environmentalists do not realise that their green technologies are not actually very green

      For example, to produce solar panels aluminium is needed and therefore lots of energy to produce it.
      Then, when time comes to get rid of old panels, industry must do so taking into account environmentally sustainable practices, which is not always possible.

      So, all factors should be counted.

      P.S. I appreciate the article, good stuff.

      report
    2. Michael Shand

      Software Tester

      In reply to Andrew Gilmour

      I would of appreciated a more constructive article rather than one stating an old argument and saying we need to do better.

      As for greenies not recognising green technologies are not very green

      It's a lame argument because everything produced in australia requires coal to be burnt......

      The solution to this isn't to not do anything, sit in a corner and cry

      but rather to move off fossil fuels

      it all comes back to moving off fossil fuels - the fact that you may need to burn fossil fuels…

      Read more
    3. Elena Berwick

      Accountant

      In reply to Felix MacNeill

      Felix MacNeill wrote: “Have you noticed the amount of embodied emissions and raw materials involved with a coal-fired power station? Have you compared them with the embodied emissions and raw materials required to generate the same amount of power through solar or wind?"

      It appears you are so obsessed with solar and wind that you cannot see anything else in the equation. Many of your arguments might be eliminated with a simple implementation of nuclear energy, which you as a specialist in environment…

      Read more
    4. Henry Verberne

      Once in the fossil fuel industry but now free to speak up

      In reply to Andrew Gilmour

      I do not regard Frlix's post as abusive as he he is not targeting you personally but he is scathing about your views. If you were labelled as a so an so x etc that would be ad hominem but I think you have nothing to really complain about.

      report
    5. Jane Middlemist

      citizen

      In reply to Felix MacNeill

      "If you ever bothered to think" etc. detracts from the seriousness of these problems and is just petty.

      report
    6. Liz Minchin

      Queensland Editor at The Conversation

      In reply to Andrew Gilmour

      Hi Andrew, Felix and others,

      For anyone wanting to report a comment as possible abuse, there's a report button next to the time stamp at the bottom of each comment. That sends an auto email to any of the editors associated with the story - and means one of us sees it sooner, rather than having to keep a close eye across multiple pages. Please don't click on it frivolously, but it's good to know it's there.

      Felix, your passion is obvious, but as you can see, comments like "If you actually bothered to think for a moment before putting that silly post together, Andrew..." aren't helpful and don't meet our Community Standards https://theconversation.com/au/community_standards, which can be summed up with the basic "Be courteous."

      By all means repost what you wrote, but without the personal commentary - just play the argument, not the man.

      report
    7. David Bindoff

      manager

      In reply to Andrew Gilmour

      Andrew A you are well informed so you know that solar panels are very green 40 to 50 times greener than coal

      report
    8. Felix MacNeill

      Environmental Manager

      In reply to Liz Minchin

      Liz, having put up with acres of Andrew's empty distractions, nonsense and insults to others, I really can't be bothered anymore.

      report
    9. Felix MacNeill

      Environmental Manager

      In reply to Elena Berwick

      So, why was my response to Andrew inappropriate or abusive, while this fact-free tripe isn't?

      Frankly, while the articles are good, the process of discussion on The Conversation is simply a waste of time.

      report
    10. Liz Minchin

      Queensland Editor at The Conversation

      In reply to Felix MacNeill

      Hi Felix and all,

      We're in the process of advertising for a Community manager, whose main job will be to keep an eye out on the comments right across the site, rather than on a sporadic basis. All of us editors currently try to do it between editing, commissioning etc, and we've relied a lot on people doing the right thing most of the time or reporting comments that are a problem.

      If there's a pattern of behaviour/problems between particular people (such as one person consistently pouncing…

      Read more
    11. Liz Minchin

      Queensland Editor at The Conversation

      In reply to Andrew Gilmour

      Felix and Andrew, can you please stop posting to each other? Do bear in mind that anyone else who's interested in this article & its content - energy-saving homes - will be getting notified every time you reply to each other & it means people simply unsubscribe (ie leave) the conversation. Which is the opposite of what we're trying to achieve.

      Sounds like the best approach would be to simply stop replying to each other; I can't see either of you winning the other over any time soon.

      report
    12. In reply to Liz Minchin

      Comment removed by moderator.

  12. David Bennett

    Architect

    Its good to see more on measuring the whole picture, but this article is problematic in a fundamental way.

    As the article sets-up nicely in its premise: "current building regulations are failing to adequately address the broad scope of energy use associated with buildings". And it's completely true. But accepting that, then the article goes on to use one key way the building industry rates 'green' - the star rating scheme - to draw the conclusion that heating and cooling loads "represent merely…

    Read more
  13. Steve Hindle

    logged in via email @bigpond.com

    Thanks for the article. It shows how we must always challenge our assumptions about energy usage if we are to find the best ways forward. Looking at the total picture often brings some surprises.
    Here is a similar story that challenges our assumptions about public transport.
    http://ideas.4brad.com/green-u-s-transit-whopping-myth

    report
    1. Jonathan Maddox
      Jonathan Maddox is a Friend of The Conversation.

      Software Engineer

      In reply to Steve Hindle

      This is cherry-picking par excellence, explicitly localised to the one country which is known for having sold off its mass-transit systems to car manufacturing companies at the knockdown price of one dollar per city tram network in order to eliminate competition in the name of the free market. I challenge you to find the comparable figures for Melbourne's highly effective tram network.

      Public transport in the USA is operated according to dollar economies as perceived through the political and…

      Read more
    2. Steve Hindle

      logged in via email @bigpond.com

      In reply to Jonathan Maddox

      You are correct, some some of examples have been cherry picked.In the link to the full essay the author explains why he deliberately put in some examples that would show some public transport to be very inefficient. He is pointing out that if planners get public transport wrong then the assumptions often made about the energy efficiency of public transport over cars can also be wrong.
      I am not going to find figures for Melb's tram system for you, I am sure you can do that yourself. But I would think it would be many times more energy efficient than the passengers using cars.
      Ironically the author works as a consultant for Google for their driverless car project. The object is to eventually develop a new transport system that has the potential to be far more energy efficient than both cars as we use them now, and many of the public transport systems. The progress in the last 5 years has been stunning.

      report
  14. Jonathan Maddox
    Jonathan Maddox is a Friend of The Conversation.

    Software Engineer

    What is going to destroy buildings, insulation materials and windows after a mere 25 years? The very assumption of a 15-25 year lifetime is a symptom of a throw-away society.

    Buildings can and should last for centuries. Windows last for centuries too. Expensive window units are typically salvaged and recycled if a building they're in is, for whatever reason, demolished.

    report
  15. John Barker
    John Barker is a Friend of The Conversation.

    Adjunct Professor at Murdoch University

    It's heartening to see a range of posts that are pretty well focused on the essay topic- where have all the trolls gone?

    Nonetheless- the important issue at point is net energy analysis- or energy returned for energy input (EROI). It applies to everything.

    An important point to me is that, although new houses need to be designed appropriately for embodied energy and recurrent energy use, the housing stock is added to at about 1.5-2% per year. Housing energy issues mainly relate to recurrent use and the energy embodied in the renovations and adornments. Therefore, domestic use of solar electricity is an important contribution- if it passes the 'superior net energy' test. Although, as I assert, we do not have definitive information on this (most of the public information is not scientifically validated), solar PV is now 'plug competitive', even without subsidies. And the cost -curve keeps on improving- at about 20% per year, compounding.

    report
    1. Jonathan Maddox
      Jonathan Maddox is a Friend of The Conversation.

      Software Engineer

      In reply to John Barker

      Net energy analysis and EROEI ratio is very important for the technology that harnesses our primary sources of energy. For energy-consuming rather than energy-producing technologies, efficiency of consumption is never quite so interesting. Pretty much every process loses energy -- indeed per the laws of thermodynamics it must -- and we're evidently quite happy with that state of affairs and take a long time to come around to the realisation that sometimes we can gain a lot by losing less energy…

      Read more
  16. Warwick Rowell

    Permaculturist at Rowell Consulting Services

    We (my son and I) have been grappling with this issue in a very practical way for some years now,

    We design for 300 years: thicker slab, no through slab fittings or wiring, better and multiple drainage, careful siting, solar orientation, breeze access, upgrade all fixings to exceed Cat 3 cyclone specs, etc. In my house, we have strawbale walls and ceilings, 95% double glazing which is fixed, 5% louvres, solar power and HWS, rain water etc etc. We have the lightest coloured roof allowed.

    Check out www.warwickrowell.com for more info

    PS we live in a mild Mediterranean climate.

    report
    1. Elena Berwick

      Accountant

      In reply to Warwick Rowell

      Warwick, this is very good.
      For some people, however, building such houses might be problematic because of cost constraints. Also, councils in lots of new suburbs in Melbourne specify the minimum home area, which makes it hard to achieve what you achieved.

      For example, if I realistically need a house of 150 sq m for my family and purchase a piece of land where I want, for this land the council specifies a minimum house of 220 sq m. This is ridiculous because of two reasons. First, I do not need so big house but I have to build it. Second, for such a big house I have more windows and a bigger slab, therefore my cost grows up. In this instance I do not care a lot about your thicker slab or double glazing as the footage of the house is big and the number of windows is around 30. So, if I follow your good recommendations I would be out of pocket.

      I think councils should not have this requirement of minimum area of the house, although I understand where they are coming from.

      report
  17. Elena Berwick

    Accountant

    This is a great article indeed. It reminds us that we have to be looking at many aspects when assessing the star rating or building houses.

    It also reminds that people sometimes are focused on delivering an immediately good environmental outcome and they might be obsessed with the great environmental idea. However, when they follow this idea, they might go to the extremes. This is probably because they assess the subject from the immediate environmental point of view and ignore a variety of factors…

    Read more
  18. Warwick Rowell

    Permaculturist at Rowell Consulting Services

    HI Elena

    You have made a number of comments that I would like to expand on. One is a touch of agreement!

    I have thought long and hard about my son's frequent opening gambit when talking to a client: "Every one of the houses we have built can be criticised, and many of the techniques we use as well." What he and you are saying is that there is no such thing as a perfectly environmentally friendly house; the transport distances, the recycling costs, the rarity of materials used, the necessity…

    Read more
    1. Jane Middlemist

      citizen

      In reply to Warwick Rowell

      I enjoyed reading the interesting discussion.
      Also enjoyed being reminded of Zen and the Art of Motor Cycle Maintenance. What a great book!

      report
  19. Mike Stasse

    Retired Energy Consultant

    It's all about ATTITUDE.......

    We live in a ten star house in Queensland. I designed and built myself.
    http://damnthematrix.wordpress.com/2011/11/01/mon-abri/

    it's rated 6MJ/m2. We NEVER heat nor cool, no matter that it's -6C or 43C outside. We don't even have a fan........ My design won an award in 2007.

    Furthermore, our last electricity bill showed we consumed 1.8kWh/day, plus we burn about 27kg of LPG and 2 to 3 tonnes of firewood a year. Firewood is the ONLY truly renewable energy…

    Read more
    1. Ivan Quail

      maverick

      In reply to Mike Stasse

      Well done Mike. The proof is in the pudding as they say. A well oriented and designed home.
      I am intrigued to know how you save money on water and sewerage fees?

      report
    2. Mike Stasse

      Retired Energy Consultant

      In reply to Ivan Quail

      100% water tanks, composting toilet, and greywater recycling.......

      report
    3. Paul Felix

      Builder

      In reply to Mike Stasse

      I refrained from making a comment bringing up the paradox of people saving energy and flying around the world in business class.
      A cousin recently visited from the UK, she was allowed a 10 min shower on each leg of the flight - I am a working builder I don't have 10 min showers!
      So thank you for your last para.

      report
    4. Jonathan Maddox
      Jonathan Maddox is a Friend of The Conversation.

      Software Engineer

      In reply to Mike Stasse

      Hi Mike,

      Jevons' paradox is no paradox at all. Wealth and growth drive increasing consumption regardless of how efficient consumption is. All else being equal, improved consumption efficiency is excellent for wealth and growth.

      Total consumption will only fall during an economic recession.

      However, the consumption of one particular resource can easily be substituted with a better one, even in a time of growth.

      If a policy goal is to reduce total consumption of fossil fuels, promoting…

      Read more
    5. John Barker
      John Barker is a Friend of The Conversation.

      Adjunct Professor at Murdoch University

      In reply to Jonathan Maddox

      Well said, Jonathan ! I think that you've summarised all the main issues besetting us. The so-called Jevon's paradox is at the heart of it. Efficiency drives will ensure that continued fossil fuel use will be technically viable and economically viable as well- externalities aside.

      But the externalities can't be put aside. That's the climate change thing. T

      The ultimate criterion is for solar and wind to be self reproducing with energy left over for other things to be done. How do we prove self- reproducibility in a complex input world? I've got a hunch that PV has now passed that point, but it's not simple to prove.

      report
    6. Mike Stasse

      Retired Energy Consultant

      In reply to Jonathan Maddox

      "despite the very real limits and increasing costs of oil extraction, improved efficiency (Jevons' "paradox") and substitution of other energy resources for oil are already proceeding rapidly and that there is no looming shortage of primary energy resources."

      REALLY Johnathon? WHAT substitutes...? The who;e point of Peak Oil and the looming Energy Cliff is that there are no substitutes, at least no equivalent ones....... Not even the crude oil we extract today is a substitute for the crude…

      Read more
    7. Jonathan Maddox
      Jonathan Maddox is a Friend of The Conversation.

      Software Engineer

      In reply to Mike Stasse

      Hi Mike,

      The means of production are nowhere near as fussy as you state about their energy sources.

      Electricity is the technology which makes energy fungible. From the 1870s we have converted the energy in running water to light, via electricity. If you stop to think about it, that's pretty miraculous. We have for a long time obtained most of our electric power by burning fossil fuels, but that was not the first energy source for electricity and it will not be the last.

      Coal and gas substituted…

      Read more
    8. Mike Stasse

      Retired Energy Consultant

      In reply to Jonathan Maddox

      "The obvious substitute for regular old fashioned petroleum is "unconventional" oil, which is increasingly conventional and is an essentially indistinguishable product despite the significantly higher costs for its production."

      It is NOT the 'COST' that matters Jonathan........ it's the ENERGY!

      Oil and coal and gas have high NETT ENERGY available after extraction. Alternatives do not. For instance, a solar panle might generate five or six times its embodied energy over 30 years, but conventional oil can give you eight to twenty times that.......

      Furthermore, you need OIL to mine coal. Your typical coal mine burns through 300,000 to 500,000L of diesel per DAY!

      Have you seen this yet?
      http://damnthematrix.wordpress.com/2013/08/09/conventional-thinking-is-over/

      report
    9. Mike Stasse

      Retired Energy Consultant

      In reply to Jonathan Maddox

      "The Great Depression of the 1930s saw hardship for many, but it also saw a huge *expansion* in the deployment of technology to make and use both oil and electricity. An energy revolution was underway the whole time."

      Yes, and guess what......... the 1930's was PEAK OIL DISCOVERY in the USA!

      report
    10. Mike Stasse

      Retired Energy Consultant

      In reply to Jonathan Maddox

      Much ado about methane
      — david @ 4 January 2012

      That's EIGHTEEN MONTHS OLD....... and things have got dramatically worse in those eighteen months, it's happening so fast that the IPCC's five year reporting cycle can't keep up.

      Did you ACTUALLY WATCH the film........ that lady Russian Scientists looked pretty upset to me about what's happening in her country....

      report
    11. Jonathan Maddox
      Jonathan Maddox is a Friend of The Conversation.

      Software Engineer

      In reply to Mike Stasse

      On the contrary, Mike, businesses actually involved in petroleum extraction account their income and expenditure in dollars, not joules.

      So long as there is sufficent *primary* energy available, extraction of high-priced resources such as copper and petroleum can continue despite the paucity of the energy return on energy investment. Mining of copper, gold, iron ore, etc. has absolutely no energy return whatsoever but that doesn't stop it happening. Nor will it stop petroleum extraction when…

      Read more
    12. Jonathan Maddox
      Jonathan Maddox is a Friend of The Conversation.

      Software Engineer

      In reply to Mike Stasse

      I don't think the fundamentals of physics or the orders of magnitude of temperature change and greenhouse gas emissions have changed in 18 months.

      The Natalia Shakhova segment quite explicitly says it's from 2012. Her words were similarly alarming and fear-inducing before that year (see her articles linked from Archer's response), and it's the legitimate questions raised by exactly those words which David Archer replied to on RealClimate in January 2012. His response took the potential "catastrophe…

      Read more
    13. Mike Stasse

      Retired Energy Consultant

      In reply to Jonathan Maddox

      No, the fundamentals of physics or the orders of magnitude of temperature change and greenhouse gas emissions have not changed in 18 months, but the sudden disappearance of the reflective ice means that instead of 90% of the Arctic solar radiation is reflected back to space, now 90% is absorbed....... and THAT will worsen the rate of change.

      I've never said that we could turn the Earth into Venus, there's not enough C on this planet to do it.

      Neither am I 'hoping' "to kill off a billion people or so"...... it's just what WILL occur, as predicted by the Club of Rome's standard run which we are currently bang on target to emulate. And let's not forget, the CoR didn't even factor in Climate Change as it was not the well known phenomenon it is today.
      http://damnthematrix.wordpress.com/2012/10/16/are-we-on-the-cusp-of-global-collapse/

      report
    14. Rex Gibbs

      Engineer/Director

      In reply to Mike Stasse

      Well not true actually. Shale oil has changed that. US is now close to being a net exporter again

      report
    15. Mike Stasse

      Retired Energy Consultant

      In reply to Rex Gibbs

      SORRY to burst your bubble......... but THAT is complete crap!!!

      The notion that hydraulic fracturing will result in American energy independence appears to have been debunked.[iv] In fact, just recently Fatih Birol, president of the IEA (International Energy Administration), has stated that the increase in American oil production is simply a surge, not a revolution.[v] To put it simply: the bold assertion of energy independence is predicated on early production numbers of shale oil wells; unfortunately…

      Read more
    16. Jonathan Maddox
      Jonathan Maddox is a Friend of The Conversation.

      Software Engineer

      In reply to Rex Gibbs

      Do you really think so?

      http://oilprice.com/Energy/Crude-Oil/US-Crude-Production-Exaggerated-in-Order-to-Keep-Consumption-High.html

      US domestic oil consumption has fallen farther than its domestic oil consumption has risen. Consumption of crude oil is down to about 18 million barrels per day from a peak of almost 21 mbpd in 2004. Production of crude is up to almost 8 mbpd, up from a low of 4 mbpd in 2006, but still way below peak production in 1971.

      The absurd thing is that bloggers are…

      Read more
    17. David Bindoff

      manager

      In reply to Mike Stasse

      I strongly suspect Mike S is correct on this one, exploration expenditures increasing strongly, production not so much; e.g.

      http://blogs.marketwatch.com/energy-ticker/2013/11/25/expenses-output-dont-add-up-for-oil-companies-ft/

      I suggest banning exploration, the net energy returns and necessary adjustments are being being held up by putting investment into the wrong area..

      Low-cost upgrades to existing housing stock and re-education on how to achieve 90% reductions in energy use should be a priority right now..

      report
    18. Jonathan Maddox
      Jonathan Maddox is a Friend of The Conversation.

      Software Engineer

      In reply to Mike Stasse

      http://reneweconomy.com.au/2013/miners-eye-multi-billion-dollar-renewables-projects-with-arena-98723

      'Off-grid mining operations in Australia tend to have electricity supplied either through diesel generation or through gas pipelines. At the diesel-supplied sites, ARENA estimates costs of around $200/MWh to $500/MWh, while at the pipeline-supplied sites around $100/MWh.

      'The former head of Perth-based Sustainable Energy Association (SEA) Ray Wills said that the diesel market alone presents a billion-dollar opportunity for renewable energy. “With over one hundred mine sites chewing 700 MW diesel a year, that’s a potential $2 billion market in WA alone,” said Wills. “The metric is that every 1 MW of solar would save almost 500 000 litres of diesel.”'

      report
  20. Paul Felix

    Builder

    We have to look at the whole picture in house design.
    Though first, in terms of increased cost, that has less to do with actual costs than the fact that the building industry rips people off. Triple glazing is too expensive here, as is double glazing, but it comes nowhere near to explaining the increases in costs. Having said that our house in the UK (don't jump to conclusions) had a full height window and door replaced with DG PVC for $400 installed. Roof design matters and materials also, but…

    Read more
    1. Paul Felix

      Builder

      In reply to Paul Felix

      By the by the house I described had no outside area for the children to play.

      report
  21. Warwick Rowell

    Permaculturist at Rowell Consulting Services

    Paul said:
    That means, if you are wealthy, you can stick a 10 kw system on your house approx $14000. You increase the capital value of your home and if you are careful in your use you can cover your total energy bill and get a reimbursement in dollars. This means that Aurora pays you significantly more than is costs them to produce.

    I have reason to believe sounds like a copout, but I have not been able to get up-to-date figures for some information that I heard in 1991. This was that power…

    Read more
    1. Paul Felix

      Builder

      In reply to Warwick Rowell

      The figures are up to date, I installed a system last Thursday and am meeting Aurora to install another this week. Next month I am installing a 10kw system.
      The way I deal with it is to ensure the systems do not exceed the expected maximum use of the premises, hence no cross subsidy.
      The issue of the poor subsidizing the wealthy in relation to domestic systems is not arguable while the feed in tariff exceeds the wholesale price.
      There are simple ways of preventing that but it means we have to look again at the way incentives for solar panels are structured.
      Better to let people like me have no incentive, cause we can afford it and instead do major energy saving programs, as in Europe, for low income people.

      report
    2. Mike Stasse

      Retired Energy Consultant

      In reply to Paul Felix

      I used to work in the solar industry. In 2010, ALL installers in Qld were offering interest free payment plans to anyone who could not afford to pay up front. I sold a system to a single woman on a disability pension who tells me she is now way better off.

      We ourselves are 'poor', by choice. We live well below the poverty line, by choice. We still managed (and the KEY word here is MANAGE!) to install 3.5kW in two steps, and the first one was by today's standards horrendously expensive, $14,000…

      Read more
    3. Paul Felix

      Builder

      In reply to Mike Stasse

      "Anyone, BTW, who 'needs' 10kW of PV to 'cover their bill' is using waaaaaaaaay too much electricity, even in Tasmania."
      I agree domestically, however a 14 room hotel uses somewhat more than a 2/3 person home, hence 10kw. See my second para.
      You may read another post where I complained that people are putting in 10kw systems so they can get a cash rebate.
      It is also the case that, much as you or I may object, people do use enormous amounts of power to run houses that are unsustainable, so a person…

      Read more
    4. Paul Felix

      Builder

      In reply to Mike Stasse

      Probably too late but I recalled this last night.
      Power in Tasmania is pretty well 100% renewable, wind and hydro.
      The only time we use gas is when the water drops too low and the only time we import power fro Vic is when the situation is even more dire.
      So for the past few years we have exported power to Victoria, which is then on sold as renewable.
      As we are not building any more dams it is probably OK to use and claim as renewable what we have, regardless of the merits of 30 years ago.
      So the only reasons for installing solar in Tas are
      1 To reduce your power bill
      2 To enable renewable power to be exported to Vic, giving a premium income stream to Tas.
      Just a though if you are planning to move to Tas. The cost of installing an off grid system buys a lot of electricity and on grid panels.

      report
    5. Mike Stasse

      Retired Energy Consultant

      In reply to Paul Felix

      Ah but you see...... I have a different mindset. I'm expecting the global economy to collapse, and the maintenance of infrastructure to suffer greatly. The price of complexity is fragility, and it doesn't take much to take the grid down, especially when you are at the end of it, which is where I want to go..... as far as possible from the madding crowd!

      You may not be aware of this (I REALLY do keep my ear to the ground....) but Aurora are ALREADY predicting that they will soon face problems…

      Read more
    6. David Bindoff

      manager

      In reply to Paul Felix

      In addition to your point 2 as a reason to install pv in TAS

      3 Basslink exports to Vic displace the dirtiest power in the country(/world? ) - if there is a continual surplus in Tas and dams are full the maximal use of basslink is permitted.

      report
    7. David Bindoff

      manager

      In reply to David Bindoff

      Also to play to Mike S's thesis, a surplus of primary energy will be required to power transport which will be required even in the (likely) event of collapsed economy. Tas imports transport fuel at enormous cost so complete energy self-sufficiency is a wise move.

      report
    8. Mike Stasse

      Retired Energy Consultant

      In reply to David Bindoff

      To add to that, Australia will be totally out of oil (on current trend - not looking like it's about to change..) and with Tasmania at the end of the supply chain, and Australia having to import 100% of its liquid fuel needs within six years, from countries that are fast growing and needing to keep more and more of their oil themselves.... it makes you wonder HOW we'll drive anywhere....
      http://damnthematrix.wordpress.com/2013/04/04/australia-still-on-target-to-run-out-of-oil-by-2020/

      BTW, it is my intention to convert my ute to electric drive once I've got it in Tasmania......
      http://damnthematrix.wordpress.com/2012/05/18/ive-bought-a-car/

      I'm even thinking of turning the car into part of the house's battery storage.......

      report
    9. David Bindoff

      manager

      In reply to Mike Stasse

      With the change from the transaction to buy in Tas you'll be able to buy a 60kWh Tesla, add a few panels and with your consumption you'll be right 'til the next ice age and be able to travel island wide for nix in style.

      I am hoping you'll ditch the concrete for the next one.
      I am concluding green timber and all tensile rather than compressive is the way to go, plus hempcrete or adobe for thermal mass and moisture moderation.

      I would like to know how you get 2kWh'day plus firewood consumption. My all-electric I am getting down to 4.5/day plus 4 for heating. I can still improve the heating, but I can't see how to get much better for cooking etc. By the time the fridge and induction cooktop, perhaps oven and a few appliances are run there does not seem to be much scope to lower that basic energy consumption?

      report
    10. Mike Stasse

      Retired Energy Consultant

      In reply to David Bindoff

      A Tesla? What....... to carry goats, haybales and a tonne of mushroom compost?

      I have no intention of ditching concrete at all, houses in cold climates NEED (ie MUST HAVE) thermal mass to stabilise inside temperature.

      Luckily, Tasmania has an unknown company that manufactures concrete that removes CO2 from the air....... and I'll be using that.
      http://damnthematrix.wordpress.com/2013/04/05/fantasising-about-our-next-house/

      report
  22. Anna Haines

    logged in via Facebook

    Having read the above posts, it's nice to see so many people passionate about what is the 'right' thing to do in this regard.

    We are currently building a house that has taken all these factors into account from the beginning. It's in no way perfect, but we have been inspired by the Tiny House movement and have considered our overall lifestyle as well as embodied energy, size and overall performance of the house. (I am finding working with recycled materials particularly adventurous, enchanting…

    Read more
    1. David Bennett

      Architect

      In reply to Anna Haines

      Hi Anna - a great source and discussion on embodied energy of buildings and many other realted issues can be found at the remarkable book "Time to Eat the Dog" by Robert and Brenda Vale. It looks at total impact by using the ultimate sustainability metric Ecological Footprint.

      It has a far more relevant rigorous methodology and comes to a different conclusion that suggested in the above article: in fact house size and operational energy is far more important to get right than embodied energy.

      The above article suffers from mistaking a "energy star rating", which is in fact a mis-named theoretical THERMAL rating. A way of measuring 'green', it AIN'T.

      If you want to look at energy USAGE (not thermal rating) by building type - have a look at data from Jason Veale at: http://www.shapingsuburbia.com/2-suburbia-now/suburbia-is-unsustainable (see graph).

      report
    2. Anna Haines

      logged in via Facebook

      In reply to David Bennett

      Thank you David!

      I'll be looking at both these suggestions.

      And I've heard that assertion before (regarding size + operation being much more important than embodied energy). Certainly from the perspective of windows, I'd strongly agree, but I still don't know that we can disregard embodied energy altogether ... I guess I'll read the book and see how convinced I become overall.

      Re star rating: Yes! I am not exactly a huge fan of the Australian rating either and paid very little attention to it while designing. At the very least the authors could have said "materials typically used" instead of "materials needed".

      But at least these ideas are out there and being debated.

      report
  23. Anna Haines

    logged in via Facebook

    While I'd be assuming your studies are more reliable, the following is easier more expressive, easier to digest and therefore probably more likely to infiltrate further through society, yet the conclusions are the opposite to yours:

    http://www.acfonline.org.au/sites/default/files/resource/index67.swf

    I'm curious - do you know much about how these figures were derived and how they reached these conclusions?

    report
    1. David Bennett

      Architect

      In reply to Anna Haines

      The ACF consumption atlas is a worthwhile tool, and its no surprise that affluence and higher ecological footprint have a strong correlation.

      What the ACF report mis-reports is the effect that building-type has once the variable of 'affluence' is removed. Of course if i am richer i'll be more likely to eat more meat, fly more often an/or further for holidays. but its not OK to conclude from this dataset ANYTHING AT ALL about the city, or housing type and its connection to sustainabitliy. One…

      Read more
  24. Warwick Rowell

    Permaculturist at Rowell Consulting Services

    HI Anna

    There are several articles on fundamentals of design, and retrofitting, on my website: www.warwickrowell.com/resoruces/articles...

    Have a look at the pattern language articles too; I have more of those lining up to go on the web-site, as I have used the concepts extensively and again on our new extension, some pictures of which appear in the sustainability article.

    For a variety of personal reasons, we have taken the opposite approach to the small houses movement; our roof area…

    Read more
    1. Jonathan Maddox
      Jonathan Maddox is a Friend of The Conversation.

      Software Engineer

      In reply to Warwick Rowell

      You make a very interesting point about fixed windows, Warwick.

      I have never yet attempted to design or build a house or to double-glaze one. When thinking about either I have looked for inspiration to housing units in Germany which are invariably fitted with plenty of openable double- or even triple-glazed windows in heavy but rather elegant standardised fittings. I would have assumed that the popularity and mass-production of such fittings would overcome much of the objection over weight…

      Read more
    2. Mike Stasse

      Retired Energy Consultant

      In reply to Jonathan Maddox

      Halve your window size... and you don't need double glazing. Half sized single glazing = a quarter of the glass, hence a quarter of the resources and embodied energy needed!

      Ever read a book by Amory Lovins called Factor Four?

      Our ten star house is all single glazed. The sun NEVER shines onto our windows in Summer, and shines through them ALL DAY LONG in Winter.

      It's so easy to achieve, you truly have to wonder what is the matter with the housing industry........

      report
    3. Mike Stasse

      Retired Energy Consultant

      In reply to David Bennett

      Define 'good'.......

      I completely bypassed architects and designed an Award winning house myself. It's a no compromise house, and it works......

      'Good' architects are virtually non existent.... though YOU may prove to be the exception to the rule David...!!

      report
    4. Andrew Gilmour

      logged in via Facebook

      In reply to Jonathan Maddox

      Re: In older units in Scotland and Eastern European countries, double-glazing is frequently achieved not by a thin and heavy sealed unit but by fully separate openable windows at the outer and inner edges of a thick external wall, sometimes fully 30cm of masonry. This is common enough in eg. Hungary that it's normal practice to use the space between the windows as cold food storage during the winter months.

      This is one of the ways to go. The second way in these countries is the use of German technology…

      Read more
    5. Anna Haines

      logged in via Facebook

      In reply to Warwick Rowell

      Hi Warwick,

      Thanks for mentioning "Windows are for light, view and ventilation, but not all windows have to do all of these!". We've done the same - working out the effective ventilation and making the rest fixed, and it seems to be a rare way to think.

      I agree that solar passive is much more than simply "lots of glass to the sunny side". There's more to it than that, such as:
      - like eaves to stop it in summer
      - strategic shading of windows in other directions
      - no need to have more windows…

      Read more
    6. Mike Stasse

      Retired Energy Consultant

      In reply to Andrew Gilmour

      Thanks for that......... I may well use that idea in Tasmania, because I like using recycled windows, and I could do that with that idea!

      report
  25. Ivan Quail

    maverick

    We already have a vast and recently gold plated electricity grid. We need clean green reliable energy.

    The Tides of the Kimberly can generate at least 6 times (300Gw) more electricity than we currently generate in the whole of Australia. Installed National generating capacity is about 54Gwatts.

    A 6G/watt (6,000Mw) bulk HVDC power line can transmit the power to Sydney for a cost of 1c per Kw hr. It is cheaper to build and operate a bulk HVDC transmission line than a natural gas pipeline…

    Read more
  26. Warwick Rowell

    Permaculturist at Rowell Consulting Services

    MY sister has a vented screen on the outside of a bale wall, and a glass front on the inside surface for about 0.5 sm of drinks storage on the south wall of her home at Bundanoon. Check out Huff.n.Puff for a ddescrition of the house. She also uses the 2delta principle: It is easier to control temperature variances if you have two walls between "inside" - where you live, and outside.. Garages, storage, guest rooms, etc..

    report
  27. Warwick Rowell

    Permaculturist at Rowell Consulting Services

    Well done Mike Stasse. It sounds from your various posts that you are a long way further down the minimal footprint path than many of the rest of us. The approx. 2kwhrs of power a day you use is pretty awesome! We have averaged 5-6 KwHrs for 17 years, which includes water pumping. As far as I am aware Australians average 20 KwHrs a day, ad in the US it is 80 KwHrs a day, so there is plenty of room there for reducing impact!

    For the purposes of discussion, and a broader consideration of…

    Read more
    1. Mike Stasse

      Retired Energy Consultant

      In reply to Warwick Rowell

      Thanks for the praise Warwick.......

      One of the great aspects of energy rating software (I'm an accredited operator) is that it allows you to optimise your window sizing. there's only one place in our whole house where I overstepped the mark, on the S facing side where we have spectacular views of two mountains. It also open out onto our deck where we entertain. On that wall we have a single glazed opening 2 m high x 3.6 m wide. And even though it faces S, on a very hot day you can FEEL the…

      Read more
  28. Warwick Rowell

    Permaculturist at Rowell Consulting Services

    On our previous house we too had a hot water system connected to the slow combustion stove - The Thermalux - Australian equivalent of the AGA. It was surrounded by 320mm of rocks, with various shelves and so on for extra space.

    A real bonus was totally unplanned. The house was long east/west, with dutch gables at either end. For more heat sharing in the house, the stove chimney went up though the roof very close to the ridge (5.1m up), and only one metre from one end. The house was totally open plan, with just a privacy wall about 3m high for our bedroom.

    The hot air rising from the stove was kicked along the ridge by the hip at the east end, hit the hip at the west end, and came down and warmed our bedroom. The process was discovered one day, when, with not much on, I stopped in the doorway into the house from the bedroom, and felt this gorgeous warm draft around my sensitive regions!

    ,

    report
  29. Warwick Rowell

    Permaculturist at Rowell Consulting Services

    HI Anna

    You say: I'd like to challenge (what I see as) your under-estimation of (truely) solar passive benefit.

    Sorry , and I don't know how you got that impression. Far from true; we couldn't live without it! Even got to the stage of using a shadow stick to find true north, when local granites shifted compasses around too much!

    We live in a benign spot; Between Dunsborough and Yallingup in SW WA,top of a hill, in the southern end of a Mediterranean climate belt - 4 - 40C temp range over…

    Read more
    1. Mike Stasse

      Retired Energy Consultant

      In reply to Warwick Rowell

      After living in a passive solar house, there is NO WAY I could go back to living in an 'ordinary' house......

      We too have a clear polycarbonate roof on our N verandah. I've installed metal slats in recycled louvre window mechanism (like this http://www.yourhome.gov.au/technical/images/44e.jpg) which are better than fixed ones because on the rare (though getting RARER with climate change!) occasion when it gets too hot to allow the sun in I can just shut them and lock the sun out altogether......

      I have to admit I hadn't thought of mirrors...... but our house, thanks to its clerestory windows is never dark.......

      It's 5:30AM as I write this, and our solar panels are already producing double our baseload....... Ah the power of energy efficiency!

      report
  30. Warwick Rowell

    Permaculturist at Rowell Consulting Services

    HI David and Mike

    Here is why I have chosen strawbale walls (and ceilings):

    With three layers of lime and sand (and some colour) you can get tonnes and tonnes of heatmass, inside R30 insulation. With one weekend's good instruction, you can DIY bales and walls, saving a lot of money. You can finish the stucco to whatever level you like; one of our clients did the first two layers with friends, then got a professional plasterer in to do the final coat.

    Heatmass: inside 50 linear metres…

    Read more
    1. Mike Stasse

      Retired Energy Consultant

      In reply to Warwick Rowell

      10 tonnes of stucco just cannot compare with 150 tonnes I have here. It's amazing how our internal block walls here on the Sunshine Coast ALWAYS feel warm in winter, and cool in summer.... it REALLY works. WHAT are your internal walls made of?

      R30 in walls is way over the top. The R rating needed in walls is half what's needed in the roof. It's also proportional to the deltaT (difference between inside and outside temperature). We have R1.5 in this house we live in now, and it STILL managed…

      Read more
  31. Rex Gibbs

    Engineer/Director

    There is a missing element here. The City apartment dwellers outsource much of their embodied energy and energy consumption. Outsourced meals, exercise and entertainment and garbage handling and other elements. Another issue is refurbishment. Suburban homes clearly have lives of over 50 years with relatively small refurbishment costs wheras the apartment has a realistic life of 40-50 years before complete demolition.

    report
  32. Alex Serpo

    Garbologist

    Yes, material efficiency trumps energy efficiency. Material efficiency is also less subject to Jevon's Paradox than energy efficiency (try the maths yourself). I wish we could integrate this principal into our planning and policy making.

    report
    1. Liz Minchin

      Queensland Editor at The Conversation

      In reply to Alex Serpo

      Hi Alex, while we appreciate your optimism, we ask everyone to register their real name. Could you please update your profile? I'll send you an email too.

      report
    2. Jonathan Maddox
      Jonathan Maddox is a Friend of The Conversation.

      Software Engineer

      In reply to Alex Serpo

      If by "material efficiency" you mean it makes sense to spend as little as possible building something, without too much consideration for how much it will cost to run and maintain it over time, and how soon it will need to be replaced, you are using too high a discount rate, ie. relying on compounded earnings from your "savings" to pay for future needs. Or you're handing problems to your descendants which you could solve yourself.

      If you mean something else, do elaborate.

      report
    3. Alex Serpo

      Garbologist

      In reply to Jonathan Maddox

      Jonathan,

      Yes I mean something else. I made the reference to Jevon because markets imply that energy almost always substitutes, but materials often don't substitute. It's a difficult concept to explain in just a few lines. My advice is to sit down with a pen + a calculator and do some scenario analsysis comparing energy efficiency with material efficiency in system change. Just try a few examples, then you'll see what I mean.

      Another way to think of it is in biomimcy terms. Ecosystems always move to maximise internal (embodied) energy and information (think of it as the thermodynamic approach to evolution). Following this natural systems will maximise material efficiency, but often as the sake of energy efficiency. The principal is scientifically sound - and if you stand under a tree in Autumn, you'll straight up observe it.

      See what I'm getting at now?

      report
    4. Jonathan Maddox
      Jonathan Maddox is a Friend of The Conversation.

      Software Engineer

      In reply to Alex Serpo

      No Alex, I still don't quite understand, but if the design principles you're expounding prefer biomimicry over corner-cutting, I'll cheerfully concur anyway :-)

      But the deciduous tree analogy doesn't cut it for human habitations. Bears might fatten up and hibernate, but It's not practical for people to just shed their leaves and go to sleep for the winter. Are you speaking of cording firewood, perhaps? That doesn't sound materially efficient to me.

      Please *define* "material efficiency…

      Read more
    5. Alex Serpo

      Garbologist

      In reply to Jonathan Maddox

      Jonathan - material efficiency is defined as the amount of material used to achieve an outcome.

      For example, in the case of transport, you might measure the amount of materials (steel, fuel, plastic) required to achieve one passenger/kilometre (note, this includes energy materials like coal, gas or oil). As you note, the lifecycle of the 'good' plays a role here, as does setting the boundary conditions of where you stop recording inputs (like the factory used to make the car/train/bus/ship…

      Read more
  33. Warwick Rowell

    Permaculturist at Rowell Consulting Services

    Material analysis is helpful at one level, but I am neither an engineer, nor a mathematician..

    Instead we focus on getting way beyond the "standard" 50 years and aim for 300 years of longevity.
    We generally upgrade all fastening materials, carefully design for versatile simple structures, add one or two layers of redundancy, and pay particular attention to ease of replacement when individual elements reach their lifespan limits.

    We fastened our roof to cat 5 cyclone specs; our present house…

    Read more
  34. Avi Ganesan

    Analyst

    This results of the analysis in this article were somewhat surprising in that 50 years of heating and cooling energy consumption for a new 6-star suburban house accounted for only about a quarter of the embodied energy used to build the house.

    However, I don't agree with the authors' conclusion that this shows a failing of the current building standards and regulations. Current standards and regulations such as MEPS and parts of the building code have made a significant impact on the operational…

    Read more
  35. Brad Kijlstra-Shone

    logged in via email @yahoo.com.au

    This is a very misleading article…

    Firstly, in the example it provides the energy consumption of the ‘inefficient’ house (which is actually a 6-star home) is only very marginally higher than the energy consumption of the ‘efficient’ (8-star) house (4854 GJ versus 4832 GJ; or 0.455%) This would be well within the margin of error of any such ambitious calculation, and could change dramatically with only the smallest change in assumptions. Not particularly convincing, but this is the basis on which…

    Read more
  36. Craig Jones

    Founder at Circular Ecology

    Interesting study. Although, from the calculations I've done on UK houses (using http://www.circularecology.com/embodied-energy-and-carbon-footprint-database.html) the low energy or PassivHaus come out a lot lower whole life carbon. I also think that the above analysis has included the electricity for appliances in the analysis, such as refrigerators, TV's...etc. If so then it's not really fair to include this in the energy analysis because it isnt related to the fabric of the building and you wont have included the embodied energy to make the appliances.

    Also on triple glazed windows you may be interested in this embodied versus operational carbon analysis, which shows that the extra embodied carbon of a triple glazed window doesn't necessarily payback, see http://www.circularecology.com/news/double-glazing-or-triple-glazing-all-pane-and-no-gain

    report