Can vegetarians save us from climate change?
When thinking about ways to tackle climate change, I usually end up drowning in the details because of the overwhelming magnitude of the issue. This is where the DECC (Department of Energy and Climate Change) Global Calculator comes to the rescue.
The calculator tool brings all of the different elements that affect the climate together in one place, making it easy to see how they interact with each other. It does this by modelling the world’s energy, land and food systems, and allows you to imagine and create your own version of the future.
Amongst many factors, you can adjust population growth, install ‘Carbon Capture’ and ‘Storage’ capabilities on all power stations, and adjust the temperature of everyone’s homes in an attempt to meet global greenhouse gas emissions targets for 2050. The tool is an open source model, which means you can even download the excel file to examine the underlying data in more detail.
There are forty different elements or ‘levers’ of energy supply and demand that you can adjust in the tool, and here is a summary of what a few of them can do.
Humans are carnivorous creatures, growing crops to feed to animals so we can eat those animals. Cutting out the middle man and eating the crops makes more sense to me. This would also be a more efficient use of land; 2011 data showed a staggering yield of 758 kcal/m2 from crop plants versus just 4 kcal/m2 from pasture-fed beef. The ’Diet’ lever allows you to see the effect our food has on the environment by adjusting the average calorie intake per person, as well as the type and quantity of meat eaten.
Aside from the positive climate impact, consciously changing our eating habits could improve our health, and tackle the uneven distribution of food consumption around the world. Finding ways of reducing food waste also plays a large role in all of this.
The ‘Travel’ lever examines how we, and our freight, move around. How far should each person be allowed to travel annually? What mode of transport should they use? Should everyone own or hire a car? Changing the answers to each of these questions in the energy calculator can have a marked impact on the predicted global climate.
Reducing the total number of cars in the world removes the manufacturing energy demand as well as the emissions associated with those additional vehicles. Alternative modes of transport are also cheaper for everyone involved.
Technology & Fuels: Fossil Fuels
Fossil fuels currently form the backbone of our energy system. Oil is used in manufacturing plastics, detergents, and cosmetics amongst many others. We also use it to generate electricity and as a transport fuel. Should we continue burning oil, or should it be saved for manufacturing? Can we switch to gas, the cleanest of the ‘dirty’ fuels?
Another powerful way to reduce emissions is to increase power plant efficiency; perhaps we can create cheap thermoelectric materials to allow effective waste heat recovery.
Technology & Fuels: Renewables This lever allows you to choose how much wind, hydroelectric, marine, solar, geothermal, energy storage and demand response you want in the world.
The concept of making electricity supply meet demand is becoming a thing of a past. Instead, we can co-ordinate to use it when renewable power is available and cut back when it isn’t. This requires us to change our habits and think about what is essential and what we can defer.
There is plenty of room here for radical ideas and innovations, for example, an area near London’s Oxford Circus is soon to line pavements with kinetic energy capturing ‘smart flooring’ by Pavegen, capturing the energy from every footstep. We could even have a global, interconnected electricity grid and capitalise on each region’s particular renewable energy strength.
Land & Food: Land use
After accounting for food production, what should surplus land be used for? Explore how different uses of land can impact climate change with the ‘Land Use’ lever. One idea is that we could grow and burn bio-crops for energy instead of fossil fuels, or regenerate forests and grassland which remove carbon dioxide from the atmosphere.
Another suggestion could be implementing ‘smart’ farming techniques that can be used to achieve the same output from smaller areas of land. Vertical farming, which is the year-round production of food in high rise buildings close to the population consuming the products, could not only reduce the pressure on land use, but would also reduce energy spend in the transport of goods.
This summary provides just a small sample of the wealth of knowledge that is embedded in the calculator. For the full experience, try it out and create your own pathway for our energy future.
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