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How is energy use changing?

To limit global warming to a聽nominally safe level of 1.5掳C as laid out in the 2015 Paris climate agreement, we must replace fossil fuels with practically inexhaustible, clean, renewable alternatives, primarily derived from sun, wind and water. The aim is to hit net-zero carbon emissions 鈥� pumping no more carbon dioxide into the Earth system than it can absorb 鈥� by mid-century.

A lot of changes will be needed before we get there. Our demand for energy is still rising year-on-year. Discounting the burning of traditional biomass such as wood, fossil fuels cover almost 85 per cent of 鈥減rimary鈥� energy demand, namely energy in its raw form, before conversion into heat, electricity or transport fuels. Of the big three fossil fuels 鈥� coal, oil and gas 鈥� only demand for coal is falling. More of the increase in primary energy consumption in 2019 was covered by fossil fuels than by renewable resources.

What do we use energy for?

Broadly, our demand for energy can be split into three main sectors, each accounting for roughly a third of energy demand.

First, there is the energy used in the buildings in which we live, work and spend our leisure time. About 77 per cent of this goes on heating (and to a lesser extent cooling). Just 10 per cent of that energy comes from modern renewable sources, which excludes things such as biomass and wood used for heating. The remaining 23 per cent of buildings-related energy use is electricity for lighting and appliances. Modern renewables supply about 26 per cent of that, with this proportion rising rapidly year-on-year.

The second broad sector is industry and agriculture. About 75 per cent of energy used here is for heat, for example in making steam to power industrial processes and for drying and refrigeration; the rest is for electricity for purposes such as operating machinery and lighting. Some of the most energy-intensive industries, for instance making steel and cement, have the lowest shares of renewable energy. Paper-making, meanwhile, covers 46 per cent of its energy needs with renewable energy.

In the third sector, transport, fossil fuels 鈥� chiefly oil 鈥� account for almost 97 per cent of all demand, principally to fuel cars and aeroplanes. Encouraging walking and cycling rather than car use can help, as can replacing petrol and diesel cars with electric vehicles, and using biofuels and hydrogen as alternative fuels 鈥� if these can be made greener.

Who is using what energy?

Three major developed economies dominate the league table of energy use per capita: Canada, the US and Australia. High car and aeroplane use, spread-out suburbs with large average home size, and high energy use for cooling and heating are all contributing factors.

Countries also acquire their energy in different ways. Australia, for instance, burns far more coal per capita than Canada or the US, with only South Africa and China coming close to this out of the larger economies.

Sweden, like Canada an affluent country with long, cold winters, covers most of its energy needs with low-carbon nuclear and hydropower. Along with France, Sweden is unusual in still having a significant amount of nuclear power in its energy mix.

Electricity generation

Renewable electricity generating capacity, especially of solar panels, has boomed in recent years 鈥� but so has demand for electricity, meaning fossil generation is still rising too. Nuclear power has also declined, so although renewables now account for 75 per cent of newly installed global electricity generating capacity, the proportion of low-carbon electricity has only increased from 35.2 per cent in 2000 to 36.7 per cent in 2020.

Getting to net-zero requires this number to be much closer to 100 per cent. This will need huge investment, not just in wind turbines and solar panels, but in transmission infrastructure, smart grids and batteries to smooth over the natural variability in electricity supply, over days and seasons, from most renewable sources.