Building Decarbonisation
Duligong Honid
Building Decarbonisation
Building operations accounted for 28% of total global energy-related CO2 emissions in 2020. With the inclusion of emissions from the building construction industry, this share increases to 38%. In this blog, we address the decarbonisation of building operations and what simple steps you can take to help.
Between 2000 and 2010, housing energy consumption increased by 14%. This trend is expected to continue due to population expansion, economic development, and urbanisation. For example, depending on various factors, worldwide energy consumption for space cooling and space heating is anticipated to rise by 7–40% by mid-century. Therefore, any significant attempt to combat climate change must consider reducing operation emissions from the building sector.
Decarbonisation means a decrease in the specific amount of carbon (or CO2) emitted per unit of primary energy consumed. For building operation emissions, decarbonisation strategies come in five main areas: behaviour change, increasing the energy efficiency of the building stock, improving the energy efficiency of lighting and electrical appliances, and switching away from fossil-fuel based heat.
There is significant potential to deliver emissions savings, just by changing the way we use our homes and offices. CCC's Sixth Carbon Budget Report's balanced pathway for buildings found that behaviour change can deliver operational cost savings in the region of £0.4 billion a year by 2050, and greater savings may well be possible. We can take a range of steps to reduce and manage energy usage in our homes and offices, saving on both emissions and bills. For example, we can turn off lights when not in use, which could deliver annual electricity savings of 0.4 TWh by 2035.
Burning fossil fuels for heating and cooling in buildings compromises the most significant part of direct emissions. Around 74% of the UK's heating in buildings is met by natural gas, and 10% by petroleum, with smaller amounts of other fuels such as coal and biomass. Heat pumps are used for effective decarbonisation of heating and cooling. A heat pump is an energy-saving technology that transfers heat without generating heat. An air-source heat pump in a residential setting can save more than 2 tonnes of carbon per year, contributing up to 20% less CO2e than gas boilers and up to 70% less than electric systems. A heat pump uses electrical energy as an energy impulse (i.e., to a compressor) to transfer heat. It takes heat from outside and warms-up the inside space even more. In cooling mode, the process is reversed, and heat is given to the outside, and the cool space becomes cooler. Of course, the input of electrical energy is required for such action.
Buildings offer abundant low-cost mitigation potential in the form of efficiency improvements. Negative abatement cost actions include switching from incandescent to light-emitting diode (LED) lighting, insulation retrofits and appliance efficiency. With LED lighting, less energy is lost to heat than incandescent bulbs, which emits fewer emissions. Buildings lose heat from doors, floors, windows, and roofs. Improving fabric insulation of buildings could reduce energy consumption from heating and reduce CO2 emissions.
However, decarbonising the building stock must look beyond the energy consumption during the use phase of the buildings. The energy used in the manufacture of construction products and during the construction process of the building also has an important role. Manufacturing construction products represent 5–10% of total energy consumption in the EU. The greenhouse emissions related to material extraction and manufacturing of construction products are estimated to be 5–12% of total national greenhouse gas (GHG) emissions in the EU. Furthermore, the material requirement of buildings currently represents one of the greatest resource use challenges in terms of the mass of resources used. Concrete, aggregate materials (sand, gravel and crushed stone) and bricks make up to 90% (by weight) of all materials used.
In this context, looking for alternatives that minimise the extraction of raw materials, incorporate recycled materials and reduce the energy consumption related to the manufacture of construction products is another way to move towards decarbonisation and a circular building sector.
At Tomson Consulting, we have rich experience in energy auditing of buildings and decarbonisation. We have provided help to numerous council's, giving improvement suggestions to various businesses to reduce their emissions and bills. Please feel free to contact us if you are interested in building decarbonisation.
https://www.sciencedirect.com/science/article/pii/S1364032114010053
https://www.mdpi.com/2071-1050/12/19/7914/htm
https://www.theccc.org.uk/wp-content/uploads/2020/12/Sector-summary-Buildings.pdf
