Emissions
Climate change is one of the biggest challenges of our time with negative impacts on the life and health of people as well as the ecosystem. Main factor which drives this change is considered to be the emissions of greenhouse gases from various activities. Housing sector is one of the most important fields as it contributes to high emissions not only during construction of buildings but also in a daily basis as their occupants try to achieve thermal comfort. In line with the above we looked at three pollutants; CO2, CH4 and N2O and assessed our base case districts, both new build and retrofit, and attempted to approximate the emissions for the following set-ups.
- Centralized boiler system (either Biomass or Natural gas)
- CHP unit district heating system
- Electrical grid network with current energy mix
- Electrical grid with 100% renewable generation
Based on the emissions data below which specifies the amount of each pollutant emitted per kWh of energy produced for the various energy sources, it calculates the total emissions of the district.
The CO2 emissions data is produced by the AEA for the Department of Energy and Climate Change (DECC) and the Department for Environment, Food and Rural affairs (Defra) while the CH4 and N2O are produced by the United States Environmental Protection Agency (EPA).
Direct emissions of CO2 are set to 0 for woodchips as the same amount of CO2 is absorbed in the growth of biomass from which they are produced. On the other hand the actual emissions during the combustion process can be found at the Woodchip (actual combustion).
It can be concluded that despite the fact, electricity heating with the current energy mix contributes significantly to CO2 emissions, as we move towards to renewables becomes the most clear and green heating approach. Moreover comparing the renewable electricity heating with the biomass which are the two arrangements with the less CO2 emissions it is clearly observed that the emissions of the other pollutants is substantially lower.
Our tool offers a user the opportunity to create districts with its own building type distribution in order to figure out the emissions associated with the three previous mentioned pollutants. The tool takes into account the heating demand of the district as well as the individual features of each district heating network's configuration like pipe losses etc.
