How does our energy use contribute to climate change?
By Yasmin Ali, Chemical Engineer
Did you start your day by scrolling through the news on your phone? Did you turn on your central heating? Did you travel by car, bus or train? All of these daily activities consume energy thereby contributing to greenhouse gas emissions, and ultimately to climate change.
Some energy needs, like charging your phone, are met by electricity. In the UK, electricity generation contributes about a quarter of our greenhouse gas emissions. The demand is met by a mix of power stations that burn coal or gas, nuclear power, and some renewable energy like wind and solar. In addition, depending on needs, interconnectors enable us to import or export electricity from and to other countries.
“A quarter of our greenhouse gas emissions come from transport”
This level of emissions is a happy story for the UK. Between 1990 and 2017, it is estimated that we reduced electricity supply emissions by a phenomenal 65%. Switching from coal to gas, which emits less greenhouse gases for the same amount of electricity produced, and installing more renewable energy generation like wind and solar farms, has contributed to this. It is also estimated that 33% of our electricity came from renewables in 2018, a record high. In addition, the share of electricity coming from coal continues to decline, with the UK planning to close all coal power stations by 2025.
“The UK government plans to end the sale of all new conventional petrol and diesel cars and vans by 2040”
But it’s not just about the supply source. 2018 saw the lowest level of electricity generation per capita since 1994; this means we are using less electricity. There are multiple contributing factors for this. The amount of electricity needed to power low-energy light bulbs and newer designs of appliances like washing machines and fridges is lower than for their predecessors. On top of that, we are becoming more environmentally conscious as consumers, looking for ways to cut our energy use.
Despite these achievements, we still have a long way to go. Another quarter of our greenhouse gas emissions come from transport. The UK government plans to end the sale of all new conventional petrol and diesel cars and vans by 2040, but what about emissions from transport trucks, ships and planes? Going forward, these have to be fuelled using renewable electricity, hydrogen, biofuel or other low carbon sources. Similar to electricity generation, this is not only about the supply source. Car sharing, cutting out unnecessary journeys, and taking fewer or even no flights will contribute to reducing emissions.
A further 14% of emissions come from the domestic sector, mainly from the UK’s vast majority of homes with gas boilers. The remainder is made up of a combination of other sources like industrial activities and farming.
Building well-insulated new homes, and retrofitting insulation to existing buildings will reduce the overall heat demand. A not-so-distant future alternative to gas boilers could be electrically powered heat pumps, as long as the electricity comes from renewable sources. Another alternative is to replace natural gas with hydrogen, but we have to make sure we’re not just kicking the greenhouse gas emissions further down the road to the hydrogen production processes.
Between 1990 and 2017, it is estimated that we reduced electricity supply emissions by a phenomenal 65%
The UK planning to close all coal power stations by 2025
It is also estimated that 33% of our electricity came from renewables in 2018, a record high.
The UK government plans to end the sale of all new conventional petrol and diesel cars and vans by 2040
Any views expressed do not represent those of the organisations I am associated with.
Yasmin Ali is a chemical engineer, working in the energy sector. She is passionate about communicating the importance of science and engineering to the public, to encourage others to follow in her footsteps.
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