By Leon Gettler
20 January 2014 — Green MashUP: The next big trend in property is the net zero energy building. These are structures with zero net energy consumption and zero carbon emissions annually. Unfortunately Australia, unlike many developed nations, has no policy on net zero buildings, which could reduce emissions big time. It’s a pity. NZE buildings could make an enormous difference.
Take for example data from the US Energy Information Administration. Almost 40 per cent of total US energy consumption in 2012 was consumed in residential and commercial buildings.
In Australia, the Department of Industry says growth in energy use in the residential sector will result in a significant increase in greenhouse gas emissions.
“The contribution of electricity to total residential energy consumption is predicted to increase from 46 per cent in 1990 to 53 per cent in 2020. Natural gas consumption is also expected to increase from 30 per cent of total energy consumption in 1990 to 37 per cent in 2020.”
Countries around the world are waking up to this trend. In 2009, the European parliament passed a recommendation to achieve net zero energy for all new buildings by 2019. The British Government has set out an ambitious plan for all new homes to be zero carbon by 2016. California has a net zero action plan to get commercial building owners to convert to net zero energy by 2030. To date, California has more zero net energy buildings than any other state in the US. Canada is also running a net zero energy pilot.
Australia isn’t even in the picture yet. There are no government policies, so for the average person zero net energy homes are not seen as good value for money.
So how does someone turn their premises into a net zero energy abode? The problem with a lot of the terminology about net zero energy homes is that it’s vague but Living Building Challenge, which is part of the International Living Future Institute, has developed a Net Zero Energy Building Certification.
The certification verifies that the building actually operates as claimed, “harnessing energy from the sun, wind or earth to exceed net annual demand.”
To get the certification, buildings have to meet the following requirements:
- Limits to Growth (in part): curbs the building’s contribution to the effects of sprawled development, which undermines the positive impact of achieving net zero energy building operation
- Net Zero Energy: serves as the primary focus of Net Zero Energy Building certification
- Rights to Nature: ensures that the building does not preclude another building from achieving net zero energy operation as a result of excessive shading
- Beauty + Spirit and Inspiration + Education: underscores the notion that renewable energy systems can be incorporated into a building in ways that are attractive and inspiring
Writing in Forbes, Peter Kelly-Detwiler says the net zero energy building movement is still nascent and has a long way to go before it becomes mainstream. But as he says, with Obama focusing on energy efficiency goals and calling for a 20 per cent reduction and with California’s NZE plans under way, it’s a trend that could take off.
To achieve this, he says an intensive planning process is critical but the key is to focus first of all on consumption.
“It’s far more cost-effective to save kilowatt hours with the use of highly efficient end-use technologies – such as efficient lighting and plug load – than it is to supply renewable energy. It’s also cheaper to utilise existing natural assets wherever possible.”
Examples of net zero energy buildings would include the Bullitt Centre in Seattle. The building has a Net Zero Energy Building certification. Office spaces are airy and bright and since most of the walls are made of glass, employees can see straight through one side of the building to the other, creating a feeling of community and openness. To encourage people to take the stairs instead of the elevator, the architects created a stairway encased by floor-to-ceiling glass walls that allow for an abundance of light with captivating views.
Technologies needed to achieve it would include high performance lighting and distributed generation such as rooftop solar.
The Ecofutures building site has a neat drawing of what a zero energy home would look like with solar thermal panels and grid-tied photovoltaic panels, a heat recovery ventilation system and super-efficient air conditioning, a solar thermal water storage tank for domestic hot water and radiant floor heating, geothermal pipes to pre-heat or cool fresh air, south facing windows for passive heat gain, recycled materials and energy star appliances. Needless to say, it’s not cheap.
The movement is gaining some momentum in Australia. Earlier this year, The Fifth Estate reported that Beyond Zero Emissions had released its Building Plan, a nation-wide plan to retrofit Australia’s existing buildings. It’s a blueprint that seeks to reduce energy in residential and non-residential buildings. It seeks to do this by retrofitting buildings with solar panels, full insulation, full draft proofing, efficient window glazing, better shading, cool roof paint, new chilled water cooling systems, improvements to air handling in commercial buildings, LED lighting, efficient appliances and energy monitoring equipment. Rejecting the use of gas, it says buildings can be heated and cooled with electric pump heating, hot water and induction cooktops.
The big problem of course is getting people to switch over to net zero energy homes when it costs money. The Australian Sustainable Built Environment Council says an additional cost of 15 per cent and a payback period of around 11 years is too long to be attractive to most consumers. It proposes mechanisms such as cash rebates for low carbon products and materials and innovative financing mechanisms, such as “pay as you save” schemes and environmental upgrade agreements. Tax concessions would also help.
But the council also flags political issues that could slow down the trend and suggests Australia is behind the rest of the world, talking about industry concerns with the quality, coverage and auditing of rating tools and regulations here. It also says differences between the states increase compliance costs and would only confuse the market. What’s needed, it says, is a broader rating tool for buildings in place everywhere so that we can develop a nationally consistent approach to energy efficiency in buildings.
Add to that the fact that Australia has been slow to adapt to the trend. Witness the Climate Institute’s findings that Australia is falling behind the rest of the world in switching to a clean economy. It’s harder to make that transition when you’re reliant on the coal industry.
Still, net zero energy plans are underway here, with the City of Melbourne planning to move to net zero energy emissions by 2020 and work under way at Lochiel Park village in Adelaide, which will have solar energy and recycled water systems as well as waste management.
As the Garnaut Review points out, all the houses there will be serviced by solar photovoltaics, as well as recycled water and gas boosted solar hot water systems. A minimum 7.5 star thermal performance rating will also be in place. There will be mandated solar PV on every dwelling, a water supply system that uses captured stormwater from a 190 hectare adjacent urban catchment, which is cleaned through a wetland system and aquifer storage recovery scheme prior to reuse in houses. As well as that, recycled and low embodied energy materials will be used in reserve and public infrastructure. That would include recycled aggregate and fibre reinforced concrete, pavers and bricks manufactured on site from recycled waste material and clay excavated from the wetlands, and use of recycled pavement products in the road base. The plan is to reduce potable water supply by 78 per cent, greenhouse gases by 74 per cent and energy use by 66 per cent, compared with the 2004 SA average.
Unfortunately, none of this will be mainstream without a clear national policy that involves the development of rating tools and audit systems assessing the sustainability of homes, targets for all new homes to be net zero energy, incorporating it into a national building framework and funding through measures like tax incentives to make these sorts of homes worthwhile. The trends overseas are clear. Australia has to do something or it will be left behind in developing a clean economy.