3 .8 Green energy sourcing

Esplanade and Photovoltaic Power Plant by racEcar_yayas/flickr.com

Electricity that is generated from renewable energy sources such as wind, solar, biomass, geothermal, and small hydro, is often referred to as ‘green power’ or ‘clean energy’. Unlike fossil fuel-based power, these sources of energy emit no or low GHG emissions. Cities around the world are taking advantage of their natural resources to source cleaner electricity. Some Cities are also trying to buffer themselves against energy price volatility and ensure energy security by supporting or generating power locally using local resources. Large cities can promote renewable and cleaner energy through the following roles they usually (not all) perform: l Distributor or delivery of energy or electricity services or supplies to its citizens l Owner of generation facilities l Regulator of things like land use or building specifications l Buyer of energy for own use l Land or building owner Local governments are significant purchasers of energy services and can therefore act as a catalyst for renewable energy projects. Leading by example local authorities also have the potential for their portfolio of buildings to provide long-term supply contracts as security for local renewable energy projects. Planning and developing local energy solutions involves exploring which combination of technologies makes most sense at different scales – looking at the opportunities for new and existing building typologies and uses and the relationship of a town or city to its rural hinterland. For example, small-scale microgeneration technologies such as solar PV (Photovoltaic) can be complemented by efficient forms of generation. There is an increasing need to focus on the role that smaller scale decentralised energy generation could play. Local (also called micro-generation, distributed or decentralised energy) energy is energy produced by individuals, businesses or communities for their own consumption, be it space or water heating, or electricity. Such ‘local energy’ encompasses a broad range of technologies that are capable of helping to reduce CO2 emissions, either because they are renewable, or because they use fossil fuels more efficiently. Examples include roof-top wind turbines, solar-heated water, and household combined heat and power (CHP) systems that generate electricity in the home and use the resulting thermal energy for domestic heating. Whilst the primary aim of such energy production is for ownuse there is also the potential for surplus generation to be sold for use elsewhere. The concept of local energy represents a fundamentally different approach to the current centralised mode of delivery for electricity. Changes in technology have reduced the cost of smaller scale means of energy production and made it easier for the networks to manage the connection of a larger and more diverse range of generating units. At a time of heightened concern over climate change and energy security, the potential for individuals and communities to make a direct contribution to tackling these issues is increasing.