This plan focusses on the reduction of Scopes 1 and 2 emissions.
Scope 1 emissions originate from the University’s direct burning of fossil fuels to create energy, which at the moment includes gas-fired boilers used to generate heat and the gas-fired Combined Heat and Power plant (in the Science Centre) used to generate both electricity and heat. Scope 1 also includes fuel for the University’s on-campus service vehicles (most of which have now been replaced with electric-powered vehicles) and the gases which leak from the air-conditioning units which we have on campus, but the main source of scope 1 emissions is currently the burning of gas.
Scope 2 emissions are the emissions released off-site through the generation of electricity from fossil-based sources (ie coal and gas-fired power stations), which is supplied through the national grid. At the moment, within the UK, about 50% of the electricity supplied through the national grid releases carbon and other green house gas emissions (but we tend to use carbon as a simpler way of conveying the scale of emissions). The remaining 50% is generated from renewable sources (mostly wind, solar and nuclear sources).
In order to reduce scope 1 and 2 emissions to zero, the main ways of achieving this are to stop using gas as a fuel source, to source electricity from external renewable sources and to generate electricity from on-site renewable sources (mostly solar). This plan sets out, in more detail, how this could be achieved.
Where it is not possible to eliminate all scope 1 and 2 emissions, off-setting may be used. Historically off-setting has meant organisations paying for off-site regeneration projects which involve planting trees (which remove carbon from the atmosphere as they grow), however these sorts of projects are now being replaced by the purchase of carbon offsets which pay for new sources of renewable energy to be built, therefore reducing the issue at source. The University would use the latter type.