3. Biomass, solar heat, and hydropower

‘Biomass, solar heat, and hydropower’ discusses three forms of renewable energy: biomass, solar heat, and hydropower. Biomass and biofuels provide energy via heat generation and food consumption. But with the rising global population, land resources are being drastically depleted, and using biomass for energy can clash with growing plants for food, and cause serious home air pollution. Solar heating for homes and industry is facing competition from electrically driven systems, but the chapter shows that the outlook for concentrated solar power is encouraging, as its cost is falling, and the availability of supply after sunset offered by concentrated solar power plants with thermal storage can be a significant advantage over solar photovoltaic farms. In a hydropower plant, the energy in water falling from a height is converted to electrical energy using a turbine. Although hydropower plants can provide large amounts of low-cost, low-carbon electricity, and provide useful energy storage through pumped storage plants, serious social and environmental issues need to be considered when deciding whether the construction of a new hydroelectric scheme is appropriate.