Reports recently published in newspapers indicate that the government’s mandatory energy star rating schemes of homes is rather inaccurate. The scheme has been heavily-criticised by the building industry (HIA and MBA) and they are calling on scientists and the Department of Climate Change and Energy Efficiency to review the way the star rating is calculated for new houses.

Applying the same software to the whole continent is not the right approach either. Most importantly there is another fundamental issue that relates to the way a home is used –which has more to do with the occupants than the actual construction of the house itself.

The main problem cited by the building industry involves the three government-approved tools used to award the star six star rating. Basically it means that there are unacceptable differences between the star ratings produced by the various software tools when assessing the same house. The flaws in the star rating system were discovered after industry representatives, private companies and scientists commissioned independent studies to test the software tools on identical houses. For example the independent testing showed that the same Brisbane house had a variation of 3.2 stars when different software tools were used to audit it. In addition the software tools are easy to manipulate to get the desired results. A side issue is the under-qualified assessors who don’t operate under any quality programs.

The second issue relates to the fact the same software tools are used Australia-wide. Since the software tools mainly deal with heating and cooling to deliver a star rating they don’t take into consideration the varying climates found in Australia. In each part of Australia there will be different contributions of heating and cooling and we have little real data to help us in our understanding of by how much, or whether at all, star ratings will help reduce consumption. A respected scientist explained that the star rating doesn’t actually measure the electricity demand in a given house. So basically there is no correlation between the stars and GHG emissions.

It has been suggested that end-use metering study should be commissioned to determine overall home energy use, energy use by home appliances and the assessment of the thermal performance of the building shell for different housing types. Also, the overall performance of the recently-built six star homes should be assessed to create a valid database to establish if the star rating scheme has in fact helped reduce energy consumption.

The third observation was expressed by a university professor who explained that in reality the behaviour of the occupants of a house dictate the energy consumption. It doesn’t matter how many stars a home has if the occupants don’t use it responsibly. It could be stacked with electrical appliances like LCD screens, fridges or with inefficient halogen lighting. The software tools merely calculate the potential savings based on the fabric of the house, insulation, wall materials and of course the likely heating and cooling. Therefore, it is really up to the individual to act responsibly and to have an interest in reducing greenhouse emissions and of course their electricity bills.

For more detailed information and pdf file go to this site: https://carbonetix.com.au/why_your_5_star_energy_efficient_home_isnt.php

(Ref: http://www.theaustralian.com.au/news/features/eco-threat-to-house-prices/story-e6frg6z6-1225904124270 and
http://www.theaustralian.com.au/news/investigations/energy-star-ratings-in-disarray/story-fn6tcs23-1225899270215 )

Last week I caught up with Raj Maniher of Baw Baw shire council in their Smith Street Community Development office that council is renting in Warragul. Raj has implemented a number of measures to cut energy use in the office, and has achieved a 30% electricity saving.

Some of the measures implemented include:

Insulating the ceiling

Double glazing using “magnetite” on some of the windows.

Getting internal reflective blinds made up by a local blind maker. Very ingeneous!

Voltage reduction on the lights

Blanking off light fittings with a clear Perspex sheet to prevent air leakage into the ceiling cavity.

Disconnecting inefficient lights and replacing with fluorescent

Upgrading to a 5 star fridge

Only switching on when needed – for example the airconditioner, and kitchen equipment is turned off at the wall when not in use.

Delamping

How would you save energy in your rented office?

On the weekend I attended the opening of the new Venny, an adventure playground for children from the ages of 5 to 16 in Kensington near the public housing estate.

The new Venny replaces an older building, and from an energy perspective has outstanding, passive-solar design.  I’d encourage other local governments to learn from the Venny with any new community facilities they are building. The key principles being:

• High levels of insulation, properly installed
• A well sealed building
• Lots of thermal mass, and a night purge system, to harness diurnal temperature swings rather than fighting them as is done in conventional building design.
• Good solar orientation.
• Solar PV to provide building energy needs.

Project architect Ralph Webster, from the City of Melbourne, summarises the building design

Ralph Weber talks about the Venny (video, 5:40)

Key energy efficient features of the building design are:

• The green roof.
  

  Venny green roof

  Coupled with the foam “sandwich panel” ceiling, the R rating of the roof is estimated to be around 11 – or nearly 3 times that of most roofs. Foam sandwich panel construction has a key advantage over batts in that its much less likely to be poorly installed, reducing insulation effectiveness.

• A 5.5 kW solar PV system
• The 50 mm foam insulation on the inside of the shipping containers around the building, including sandwich panel on the roof to improve its strength and ability to take the load of the green roof.
  

  insulating board lines the containers

• The high quality windows, with an aluminium weather proof external finish, but the rest timber (so the frame provides a good thermal break). Glazing is double, low-e, with argon fill.
• High thermal mass in the concrete floor. The floor is spectacular, a key feature of the building, incorporating children’s art, building plans, etc, encapsulated in the floor with a clear resin coating. (I’m not sure how the coating influences the performance of the thermal mass)
  

  Venny floor

• Use of a phase change material (PCM) in the plaster. A 10mm plaster thickness essentially has the same thermal mass as a 90mm brick. The PCM is a BASF product called Micronel, that is encapsulated in the plaster. At 26 degrees it changes phase from a solid to a liquid, absorbing a lot of energy as it does so (just like making ice requires a lot of energy).
• Sensor controlled lighting, which is a combination of metal halide and T5.
• Aggressive occupancy sensor timing settings on the toilet lights and fan, with a 5 minute timeout.
• A night purge. This is used to “recharge” the PCM in the plaster. So for example on a hot summer’s day the PCM may have all melted. By having cool air pass through the building at night it “recharges” (ie solidifies) the PCM. The night purge consists of a couple of windows that open at ground level and a ceiling vent that opens at night. There is provision to install a fan if necessary. The use of a night purge has been the single best feature of Council House 2.
  

  phase change material (PCM) in plaster ceiling

• Ceiling fans to provide cooling via air movement if necessary
• High efficiency gas wall heater with a balanced flue.
• Exact due North orientation, minimal use of east and west glazing.
• Focus on recycling materials (such as shipping containers) for low embodied energy.

CarbonetiX has been involved with the Venny with the provision of a real time monitoring system to track site electricity consumption and solar electricity production, and also to monitor performance of the green roof. Three different substrates have been used in the green roof on a trial basis. We have put temperature sensors in the substrates and are also measuring water use to each section of the roof. This will be used to help evaluate the performance of the different substrates, which is a research project being undertaken by the University  of Melbourne.

The hope is that the building will be a net exporter of energy. What I particularly like about the Venny is its sensible passive solar design, and reliance on simple control (just using the fire panel). Its easier to keep energy use low in a building where the controls are simple and easy to understand.

I would like to install some more sensors to monitor and understand the Venny’s thermal and energy performance in more detail, and Ralph is happy for us to do this, with the University of Melbourne probably available to assist with installation and data analysis. This will help us better understand the effect of the various factors that interact to determine the whole building performance, of use when looking at retrofit options for existing buildings.

If you know of anyone who might have research funding available for this let me know!

And if you are building a new community facility, please get us involved. I have a great personal interest in zero energy buildings, which I believe are possible with today’s technology. With good design believe a zero net energy building can be cost competitive with more conventional, energy inefficient, construction.

Mal Oldis, an earlier innovator with LEDS, contacted me recently with the following comments on our report LED as a fluorescent substitute:

I have read with interest your assessment of LED lighting vs Fluorescent lighting. Well done!!
I have done much work with LEDs and yes, much credibility is lost due to false and exaggerated claims.
Indeed a company for which I was in charge of product development, failed partly due to exaggerated claims.
I probably built the first LED replacement (in Australia)  for a T8 over 10 years ago.
I learn t much from Agilent’s LED division in San Jose and also from the team at Philips in Holland.

Can I comment on your (very good) report?
I am not suggesting that you do not understand these issues, but there is some technical issues that commonly do not seemed to be explained to potential LED users.

Life time issues. Rated life time for LEDs and Fluorescent lamps is very different but the same term is used.
Rated life time of fluorescent lamps is usually stared time taken (under specified switching cycles) for half the lamps (median life) to fail.
Between 6 to 30 thousand hours are possible.

The rated life under these conditions for most LEDs is around 1.4 million hours. The “life time”  quoted for LEDs of say 50,000 hours (typical for white) is the 50% radiant (photometric) output level. It is interesting to note move to 70% output as noted in your report.

It is common to use the LOR (Light Output Ratio) figure for luminair directly. Also lumen maintenance can vary considerably for a luminair that uses fluorescent lamp due to dust and other contamination on the tube and the reflector, which forms part of the secondary optics.
Any  secondary optics (diffusers etc) using LEDs is simpler and therefore more efficient.

When I talk of the economics of LED lamps, I create an economic model and refer to cost of ownership which includes various maintenance regimes.

Also there is often no mention of the spectral properties, notably the Color Rendering Index which is poor for Fluorescent and even poorer in LEDs.

I did the original engineering for the BP Neon replacement for the service station canopies, and did much work with the City of Port Phillip using LEDs for public lighting.

Cheers,
Mal Oldis.

I’ve been invited to comment on a recent article by Hunter Richards of Software Advice on greenwash. The article calls for an improvement to environmental accounting infrastructure through software, so that consumers can have greater confidence in claims of carbon neutrality.  Financial accounting methods, standards, auditing procedures and tools are well developed, but not so with carbon accounting. By way of example Richards highlights how a well known company that stated it was carbon neutral hadn’t accounted for its scope 3 emissions.

Scope 3 emission are “indirect” emissions that are embodied in products and services that a company may use. For example scope 3 emissions for a drinks manufacturer would be the carbon emission embodied in the aluminium the drinks company makes its cans out of. However the Greenhouse Gas Protocol, the major global carbon accounting standard in use, hasn’t yet prescribed inclusion of scope 3 emissions in carbon accounting practices

Scope 3 emissions are challenging to measure, and ultimately can only be accurately tracked if every product is labelled with its embodied carbon emissions. Financial accounting practices rely on everything having a price. For example, the sale price of a car is comprised of the cost of everything that goes into making the car, down to the wheel nuts. The price of the wheel nuts in turn depends on the price of the steel used to make the nuts, and the amortised cost of the tooling used to make the nuts. The price of the steel depends on the ingredients in the steel, for example its molybdemum  content, amongst others. The price of molybdemum depends on the cost of energy and labour and amortised machinery used to mine it, process it and transport it. The amortised price of mining machinery depends on many factors as well. Ultimately there are probably well over a million prices that come together to make up the price of a car. In the same way complete carbon accounting also relies on every product or service having emissions associated with it accounted for.

This is complex to do. Daniel Goleman’s book Ecological Intelligence gives the example of glass, which typically has over one hundred ingredients in it in addition to sand. To provide thorough scope 3 carbon accounting requires being able to identify the emissions arising from each ingredient. Thorough scope 3 accounting for something like a computer or a mobile phone is thus very hard to do if the embodied emissions of each constituent part is not known. In the absences of mandated carbon labelling for all products and services, voluntary carbon reporting of scope 3 emissions is very challenging.

This is where emissions databases, and associated software, are useful. “Generic” emission factors could be developed for a particular type and size of product or service, in the absence of actual numbers, and applied when estimating scope 3 emissions. Global sharing of this information via on-line databases could make scope 3 carbon accounting much easier. However generic emission factors will only ever be rough approximations. Ultimately if accuracy is the aim everything in the economy needs to be labelled with its carbon emissions.

Standards, auditing standards, certification schemes and clear rules are needed for accurate carbon accounting. In the absence of complete carbon labelling of everything there needs to be transparency around methodologies and recognition that scope 3 carbon accounts will at best be estimates with a long list of assumptions behind them.