Think Big: How to reap the greatest gains in energy and materials efficiency

The human race could reduce its energy use by 75 per cent by redesigning vehicles, buildings and other so-called passive systems, according to Julian Allwood, reader in engineering and leader of the Low Carbon Materials Processing Group at the University of Cambridge. “Our passive systems are highly inefficient. We haven’t given much attention to those,” Allwood told a Science|Business academic policy symposium in Brussels on September 28th.

Much of Allwood’s research explores how governments can design solutions that have large-scale impact on climate change, energy use and resource efficiency. In a recent book, Sustainable Materials: With Both Eyes Open, he notes that five key materials account for 55 per cent of industrial emissions:  steel, cement, plastic, paper and aluminium, according to data compiled by the International Energy Agency.

One conclusion is clear: the battle against climate change may depend on a much tougher stance on resource consumption. Allwood’s work on life-cycle analysis highlights where the biggest gains can come, and flags false savings calculations – such as shutting down coal-fired power plants and then importing electricity. To date most of the reductions in greenhouse gas emissions in the EU have been achieved simply by exporting production to other countries, according to Allwood. Measured in terms of consumption, the EU’s emissions continue to rise, he said.

Wasting less energy and materials could yield multiple benefits for Europe – cutting greenhouse gas emissions, lowering Europe’s dependence on energy imports, reducing the strain on limited natural resources and increasing geopolitical stability. In many cases, the technology exists to reap big gains, but governments need to encourage markets and consumers to behave differently.

Lighter vehicles 

Allwood said that the average vehicle in the UK achieves 35 miles per gallon, even though Volkswagen has developed a car that can do 200 miles per gallon. Noting that energy usage is directly proportional to the mass of the vehicle, Allwood said policy makers should focus first and foremost on making cars lighter, rather than simply encouraging the use of electric vehicles.

Buildings could also use far less steel, cement and other energy-intensive materials, Allwood argues, offering a huge potential savings of energy and resources. “The Eurocodes building regulations specify a minimum material requirement for safe buildings, but we are gathering evidence that suggests we are generally exceeding this minimum by up to a factor of two,” he said in an interview on the sidelines of the symposium. “We should also keep buildings longer,” he added. “In Britain, the average new building lasts 40 years, even though it was designed to last 100 to 200 years.” Buildings are torn down either because the user's need changes or new planning regulations allow high-rise structures to be built, for example, Allwood added.

So what is preventing the use of much lighter vehicles and buildings? The answer is market forces. People prefer to buy heavy vehicles because they are larger and have more luxury features, while builders use more materials than they need to because this approach reduces their labour costs, Allwood says.  He believes regulators need to intervene and mandate the construction of lightweight vehicles and buildings. To try and nudge governments into action, Allwood is looking to demonstrate the value of lightweight homes. “I am looking to find lead users,” he said. “I am looking for wealthy individuals and senior executives who want to do the right thing.”

Although relatively little new housing is being built in Europe (just one per cent of the total housing stock in the UK, for example, turns over each year), Allwood believes the introduction of lightweight commercial buildings could have a significant impact on the energy used in the construction sector. Policy makers are thinking along similar lines. In September 2011, the European Commission published The Roadmap to a Resource Efficient Europe, which calls for all new buildings from 2020 to “be nearly zero-energy and highly material efficient.”

Manufacturing waste 

In the industrial sector, manufacturing processes tend to be quite energy-efficient, primarily because of the need for companies to cut costs to remain competitive. But that doesn’t mean materials aren’t wasted. A study by Allwood and his colleagues at the University of Cambridge found that one quarter of the steel made each year never makes it into a product. As labour is far more expensive than raw materials, the steel industry makes an intermediary product from which its customers can cut out the specific components they need. The residual scrap is recycled, but this requires a great deal of energy, and new processes could potentially create less waste, according to Allwood’s research.

Although regulation may well be required to persuade manufacturing and construction industries to change their processes, Allwood believes technology could offer new solutions. “Techniques developed in the textile industry to make the maximum use of the material could be applied,” he said. He and his colleagues are researching whether this technology can be adapted for use in the steel industry.

In practice, resource efficiency often boils down to making more effective use of energy, which can be used to both extract more materials and recycle more water.  Yet, parts of the global economy waste energy on a massive scale. “We could live well with half of the steel we are using now....we could make products lighter, keep products for longer and reduce the yield losses,” Allwood noted.

Some governments (including the UK government) believe that rising prices, either through market forces or taxes, will drive both consumers and companies to become more resource efficient. The European Commission’s Roadmap to a Resource Efficient Europe says that by 2020, there should be “a major shift from taxation of labour towards environmental taxation.”

Although Allwood sees the logic, he is sceptical.  “The whole tax structure is set up to punish labour rather than materials,” he told the symposium. “To reduce emissions, we would have to replace tax on labour with materials...that is a nice, theoretical concept, but it would be a long journey to put that in practice.”

Regulation needed 

To change industrial processes governments would have to dramatically increase the tax on materials and dramatically lower the tax on labour. But to avoid a major reduction in public-sector revenues, the material taxes would have to be extraordinarily high, Allwood argues. “Pricing mechanisms (in industry) won't work,” he concludes. “They might work in transport – people drive less when petrol prices rise – and for heating homes, but they will have no effect in industry, because the impact is small compared to the cost of labour.” In many cases, regulation may be the only way to make industries more resource-efficient, Allwood said.

To underscore his argument about the need for behavioural change, Allwood is giving up flying for a year to cut his carbon footprint. Rather than accepting invitations to speak in person at conferences in Japan, China and the U.S., he is offering to speak via video link. Within Europe, he takes the train. Says Allwood, as he gathers his bags to return to London by rail:  “There is a disconnect between flying around the world and speaking about the need for cutting carbon emissions.”

Allwood spoke at Resource Innovation: New ideas for managing scarce resources and energy, the fifth in a series of Science|Business policy symposia supported by BP on aspects of low-carbon energy and resource innovation. Background on this event and reports from the series are available online.