A new report out today from Rapid Transition Alliance founding member the Centre for Alternative technology (CAT) looks at how the UK can cut energy demand by 60% and reach net zero greenhouse gas emissions using current technologies, without relying on unproven carbon capture.
By modelling the changes needed to energy, buildings, transport, industry, diets and land-use, ‘Zero Carbon Britain: Rising to the Climate Emergency’ clearly demonstrates that we already have the tools and technology needed to play our part in leaving a safe and habitable climate for our children and future generations.
People all over the world are feeling the effects of climate breakdown, from unprecedented heatwaves, droughts and massive wildfires to some of the most damaging floods and storms ever seen. The warnings from the scientific community are now becoming real life experiences.
The current UK greenhouse gas emissions target of net zero by 2050, though ambitious in comparison to some other countries, does not offer rapid enough reductions to provide a good chance of avoiding extremely dangerous climate breakdown. Neither does it adhere to what might be termed the UK’s ‘fair share’ of the remaining global carbon budget.
By making changes to our buildings, transport systems, land use and behaviour, and by investing in a variety of renewable energy technologies, we can achieve a zero carbon transition while building in a wide range of additional benefits.
CAT’s new report provides a blueprint to open new conversations around the scale and speed of change we need to deliver if we are to rise to the climate emergency. It can be used as a template to help citizens and local and national policymakers develop and deliver zero carbon action plans.
By using energy more efficiently we can power down demand by 60%. At the same time, we can power up the UK’s renewable energy resources to replace fossil fuels. And by making changes to our agricultural systems we could then balance out the remaining 8% of emissions from non-energy processes (such as cement production or methane from livestock) by removing greenhouse gases from the atmosphere through natural carbon capture from forests and restored peatlands. This would take us to net zero emissions overall.
Our current lifestyles use far more energy than we actually need. CAT’s research shows that we could reduce our energy demand by around 60%, with particularly large savings in heating buildings and in transport.
It is possible to supply 100% of the UK’s ‘powered-down’ energy demand with renewable and carbon neutral energy sources, without fossil fuels and without nuclear.
In the Zero Carbon Britain energy scenario:
The important question for a 100% renewable energy system is not if we can produce enough energy but whether we can produce enough energy at all times – even when the wind isn’t blowing, the sun isn’t shining and our energy demand is high.
Hourly modelling of the renewables mix in the Zero Carbon Britain scenario shows a surplus of energy 74% of the time.
We ensure there is enough energy at other times by:
This research suggests ‘baseload’ power that provides a continuous supply of electricity but can only respond slowly (nuclear, for example) doesn’t work well with a highly variable renewable energy system, as it leads to further overproduction when renewables already exceed demand.
The Zero Carbon Britain energy model is one of the most detailed studies to date on balancing demand and supply in a renewable energy system. It uses hourly weather data (sunlight, wind speeds, temperatures, etc.) from over the ten-year period of 2002 to the end of 2011 – a total of almost 88,000 hours – to test renewable energy mixes under real life conditions
Energy flows in our scenario – from supply to demand (figures are in TWh/yr)
Through ‘powering down’ demand and ‘powering up’ renewable supply, the UK’s emissions can be significantly reduced save a few industrial and waste management processes that still emit residual greenhouse gases. However, there are also emissions associated with food production, land use changes and land management practices – this accounts for around 10% of current UK emissions.
Agricultural systems are threatened with reduced productivity due to a decline in the numbers and variety of plants and animals in farmland and the surrounding environment. This variety of life is necessary for efficient food production. Therefore, our land management practice must include restoring essential biodiversity.
Our model explores how we can achieve this whilst also reducing agricultural emissions, providing a healthier mix of foods, reducing unnecessary food imports, producing building materials, providing UK sourced biomass, and increasing natural carbon capture to ‘balance’ our residual emissions. In doing this, the UK will become more self-reliant and can clean up its own mess within its own territory. This is a vital piece in the net zero carbon jigsaw.
The use of land explored in the Zero Carbon Britain model will offer a healthier mix of food, plus backup energy supply, and will provide natural carbon capture, which allows the UK to be truly net zero carbon.
Through dietary change, food waste reduction and improved agricultural practices we could provide a healthy, sustainable diet for the whole UK population.
These changes would mean that:
The modelled dietary change contains significantly less protein from meat and dairy (which have high emissions and use a lot of land) and more from plant-based sources like beans, nuts, cereals and vegetables.
The Zero Carbon Britain food and diets model combines data describing the nutritional qualities of the foods we eat, their land requirements and the greenhouse gases emitted in producing them. This model can then be used to assess the impacts of dietary change.
Making these changes would mean that we have enough land in the UK not only for producing food but to offer new potential income streams.
As well as being used directly as a fuel, UK sourced biomass can be combined with hydrogen from surplus renewables to make carbon neutral synthetic gas and liquid fuels, which increases the amount of fuel produced per acre of land. These are ‘carbon neutral’ as the greenhouse gases they contain were initially captured by the biomass as it grew, resulting in no net increase in the atmosphere.
Forest area is doubled to 24% of the land area of the UK – roughly one third is unharvested and two-thirds harvested for timber. These forests, the wood products they produce and the restoration of 50% of UK peatlands, results in the capture of around 47 MtCO2e on average every year. This is required to balance the residual emissions in the scenario and so make the UK net zero carbon.
The changes would also provide more room for biodiversity in wild, restored, conserved or protected areas.
A great many people and organisations across the UK are working alongside their local governments to explore zero carbon transitions in transport, energy, buildings, food, land use and waste. Not only can we deliver this through collective action plans, we can also make the individual changes which directly reduce our own emissions, and so transform how we relate to climate breakdown personally.
How you use the report will depend on scale, location and circumstance, but here are some common approaches:
While the impacts of individual changes are, of course, relatively small, as more and more of us scale these up they normalise emission reduction behaviours, empower people, help change social and political norms and so increase ambition for policy shifts.
Sharing Zero Carbon Britain can inform ambitious practical actions and policy shifts by clearly demonstrating:
Clearly, there is no single technology, policy or action that can prevent climate breakdown. It will require many people, from all walks of life, working together to bring about the change we need to see.
So let’s come together at individual, local, national and international levels – and collectively rise to the climate emergency!
You can read the full report on the CAT website, where you’ll also find a range of resources for sharing solutions, including graphics, videos and suggested posts. www.cat.org.uk/zcb