This publication provides technical guidance for the preparation of SAP proposals. Renewable energy (RE) is produced using natural resources that are constantly replaced within the human timescale. Just as there are many natural sources of energy, there are many technologies that can help to harness RE sources. Solar photovoltaic (PV) is the most well- known, wind power is the most widespread and hydropower is one of the oldest. Other RE technologies harness geothermal energy, solid waste or ocean-wave energy to produce heat or electricity.