Carbon emissions reduction is a common aim of the world’s governments.
However, most of them are failing to reduce the huge quantity of carbon emissions from constructing and using buildings.
A Good Example?
Architecture students will probably throng to Norway’s Brumunddal (a town of 10,000 people) to visit the 85-metre-high Mjostarney tower. Following SpaceShaper’s blog last week looking at timber construction and the ethical use of timber as a low polluting material, this seemed the most appropriate example.
The Mjostarnet tower looks like a naked tree, with its pine cladding and supporting columns made of glulam-wooden beams. These are lighter than steel and of comparable strength but require only 1/6 as much energy to produce. Most of the wood comes from sawmills and spruce forests within a 50km radius of the site. As such, creating and transporting materials for the tower emitted a few greenhouse gases. Could this be the future of construction?
Building Energy Consumption – The Facts
Ever since Romans began to build with fired-clay bricks and concrete, construction has been a polluting industry. The International Energy Agency estimates that putting up and running buildings consumes 36% of the world’s energy and produces some 40% of energy-related carbon emissions. 5/6 of that energy is used to light, heat, cool and run appliances.
Consider the energy that goes into producing construction materials and the share of emissions from buildings is even higher. More than 5 billion tonnes of cement – the raw material for concrete and mortar – is produced each year, adding a further 6% of emissions. The steel industry, half of whose production does into construction, accounts for another 8%.
Government Commitments are not being met
In 2015 world leaders pledged to keep global temperatures from rising more than 2 degrees above pre-industrial levels. That would entail drastically cutting emissions associated with buildings. So far, progress has been slow. Some things, like domestic boilers and lighting, have become much more efficient. Others have not. Under current regulatory framework, for example, emissions from the cement industry will rise 4% by 2050 if policymakers take no further action, according to a report published last April by the IEA and the Cement Sustainability Initiative.
The obvious way to make buildings greener is to impose a broad carbon tax, covering everything from household energy use to the emissions embodied in building materials. But any levy that visibly raises energy bills will be unpopular.
One problem is that the poor feel the hit from green taxes especially hard. They tend to live in the least efficient homes and struggle to afford better insulation, which would cushion them against rising prices. Also, many people will keep their homes toasty no matter what.
Policymakers have tried offering subsidies and loans for rooftop solar panels and energy efficiency improvements that are repayable with the savings from lower energy bills. Britain has a Green Deal. Unfortunately, take up has been much lower than people expected, partly because the expected savings did not materialise. A government study contradicted the claims in Britain that installing loft insulation can cut energy bills by 20%. In fact, it found that it reduced gas consumption by just 1.7% on average.
A New Policy to push Progress
Many rich governments have created rules forcing developers to build new projects to “zero energy” or “zero carbon” standards.
Through a combination of
- energy efficiency measures,
- on-site renewable heat or power generation
- and buying offsets elsewhere,
new buildings should cover all their energy requirements from renewable sources.
From January 1st 2019, EU countries must build all new public sector buildings to “Nearly Zero-Energy” standards.
Other types of buildings will follow in January 2021. Parts of America and Asia are following. In Japan the government wants zero energy buildings to become the standard from 2020. Last month the Canadian province of British Columbia passed a plan requiring that all new buildings from 2032 must be built to these standards. Governments in countries such as New Zealand are being lobbied to copy them.
The technology to build and retrofit buildings to cover their carbon footprint already exists as you will be able to see from our SpaceShapers Low Energy Services Page. Indeed, sustainable accreditation systems have been developed around the world to assist designers and constructors to achieve low energy standards with BREEAM (UK); LEED (USA); Estidama (UAE).
The reality of the situation
Construction is one of the world’s most fragmented industries, with fierce competition between small firms for contracts. With thin margins, developers and builders are unlikely to build greener than they have to.
One must also question whether concentrating on new builds is realistically going to reduce the energy consumption across the built environment. The policy focuses on new buildings and does little to cut emissions created by older ones.
In the developed world, each year only about a new one in 100 existing buildings replaces one.
Many zero carbon buildings are neither as efficient as they should be, nor do they generate as much renewable energy as they would have to.
This is due to a lack of knowledge throughout the design industry regarding how energy actually flows through a structure. Instead, this is essential if you are to mitigate the energy that we waste.
A solution and back to trees!
If Governments would change zero carbon standards to include the emissions from building and demolishing the structure, many of the perverse incentives in the building regulations would disappear. It would probably lead to more building with wood. Many mature forests do little to take extra carbon out of the atmosphere. Chipping some of them down, storing the carbon in wooden buildings, and planting new trees in their place could well increase forestry contribution towards actually removing carbon.
If you would like SpaceShapers Low Energy Design team to assess your building or project to meet “zero carbon” or “zero energy” requirements, please contact us.