Frequently Asked Questions
What Is Renewable Energy?
Renewable energy is derived from sources that are not depleted when they are used, such as hydro, wind and solar power.
What Are Renewable Energy Sources Used For?
Typically, renewable energy sources can displace conventional fuels in the generation of electricity, the generation of heating and hot water, transportation, and the provision of rural (or off-grid) energy services.
How Much of the World’s Energy Is Currently Derived from Renewables?
According to The Breakthrough Institute, around 9% of the world’s primary energy is derived from renewable sources. In 1800 this figure stood at 100%, in 1900 it was about 60% and in 1950 the figure was 38%. Today, some countries get the majority of their energy from renewables, such as Brazil, which gets 75% of its electricity from hydropower.
Why Are Renewables So Important?
As finite resources, fossil fuels like coal and gas will almost inevitably run out one day. Therefore, it is vital for countries to develop and use alternative, renewable energy sources to meet their power and heating needs.
How Efficient Are Wind Turbines?
Typically, wind farms generate electricity 80-85% of the time. This power is converted to electricity efficiently and without the thermal waste inherent in the generation of power from fossil fuels.
What Is Geothermal Energy?
Derived from the internal heat of the Earth, geothermal energy has been used in some countries for thousands of years for heating and cooking. Some buildings are now fitted with geothermal heat pumps that use temperature differences (several feet below ground) for heating and cooling, while on a larger scale, underground reservoirs of hot water and steam can be tapped through wells that run a mile or more deep to generate electricity. Unlike wind and solar energy, geothermal energy is always available, but its generation has side effects that need to be taken into account, such as the release of hydrogen sulphide which results in a rotten egg smell.
What Is Marine Energy?
Marine energy (or ocean energy) is energy carried by ocean tides, waves, ocean temperature differences and salinity. The movement of the oceans creates a store of kinetic energy that can be harnessed to produce electricity to power homes, industries and transportation.
Do Biofuels Have the Capacity to Significantly Scale Up?
Despite the fact that today we have more technologically advanced ways of transforming biomass into transportation fuels, little progress has been made in improving the land efficiency of biofuel conversion and production. Particularly advanced technologies aiming to produce fuel from algae and other microorganisms could provide the answer, but such technology is still speculative.