Zero Carbon Britain – Rising to the Climate Emergency

By Kevin Boon

“I’m as impressed as ever. I love the fact that you literally encompass the whole of the economy, rather than going after the easy bits!”

Jonathon Porritt on Zero Carbon Britain.

Founded in 1973 on a disused slate quarry in Mid Wales, the Centre for Alternative Technology (CAT) has evolved from a community to a visitor centre to an educational charity specialising in sharing practical solutions for sustainability. CAT was founded on the basis of a new role for technology, focusing on benefits to humans and nature as well as to economies.

The 2019 Zero Carbon Britain (ZCB) report considers challenges to meeting a net zero 2030 target for the UK based on where the country currently is in terms of carbon budget. They estimate that, based on the UK government’s legally binding carbon budget figures, existing policy targets mean that we will have only a 50% chance of meeting a 2oC target. The report methodology includes only technologies that are in current use or have been demonstrated to work. It does not consider nuclear power a sustainable option or the use of carbon trading. Unlike the Kyoto Protocol, it does take account of emissions from international aviation and shipping. CAT’s approach is based on the UK being nationally self-sufficient in energy and food. The economic cost has not been calculated. 

In calculating future emissions associated with energy generation they believe that demand can be reduced by about 60%. In the case of buildings (41% of total 2017 energy used) retrofitting insulation could reduce average heat loss of housing by 50%. There is also a need for more efficient and smarter appliances. Solar-heated hot water and geothermal heat can meet some of the energy required, but most will be met primarily by heat pumps.  In some cases, biomass or direct electric heating systems may be appropriate. 

Industrial energy use, comprising 15% of 2017 total energy, has declined due to a combination of changes in goods produced and increased imports. There is a need to reduce demand (eg recycling, repairing), change production (eg less iron manufacture) and improve efficiency. Carbon neutral energy sources will be required such as synthetic gas, biomass and biofuels. Heat stores (for example tanks of hot water) are also part of the solution. 

Transport makes up 41% of 2017 total energy with about 50% of the total relating to surface passenger transport. Moving forward, it is important to increase walking, cycling and use of public transport. A switch to efficient electric vehicles is essential however some vehicles, as well as ships and aeroplanes, will require carbon neutral biofuels or synthetic liquid fuels made from biomass combined with hydrogen. The impact of freight-related emissions would be reduced by importing less and using rail rather than road. Fully electric aeroplanes are not currently viable but hybrid planes are being developed as are electric powered ships. 

Currently around 80% of the UK’s energy needs come from fossil fuels. CAT believes that our future requirements can be met by 100% renewable energy. In their scenario, around half of this would come from offshore wind turbines. The balance would be made up of a mix of sources including on-shore wind, wave, tidal and hydropower. Biofuels and ambient heat (extracted from ground, water and air by heat pumps) also play major roles. Other contributions are made from solar thermal and geothermal heat. Energy demand management and storage solutions would be needed to match supply and demand. There would be a need to shift consumption patterns to reflect energy availability. CAT based their work on real weather data from the previous 10 years. 

The non-energy emissions from industry, businesses and households accounted for 6% of the 2017 total. CAT proposes ways of reducing them for example changes to industrial processes such as using different raw materials. The report also considers how to minimise emissions associated with waste management in particular landfill. 

The CAT scenario envisions a dramatic change in land use to facilitate more self-sufficiency in crops, provide energy resources (such as biomass, short rotation forestry, grasses) and significant carbon capture to offset any residual GHG emissions. Key to this would be dietary changes, which are considered in detail, resulting in a four fold reduction in grassland for livestock and significant reduction in land for livestock feed. 

The CAT approach reduces emissions from 2017 levels by 91% with the balance being removed by carbon capture.  To this end they propose doubling the forested area of the UK, enabling harvesting of more timber to use in buildings and infrastructure, restoring 50% of peatland, and converting waste wood either into biochar (a form of charcoal) or leaving it in ‘silo stores’. Land use changes will also improve biodiversity. 

The report also considers policy, employment and economic issues as well as wider societal benefits. There are also sections on adaptation to built-in climate change and planetary boundaries.  CAT also present variations to the net zero scenario and discuss the different accounting approaches to emissions. The report ends with a section on using ZCB. This looks at changes in ways of thinking, individual action, influencing policy, education and developing action plans. 

The report can be downloaded here: