This is a very short guide that outlines the definition of renewable energy, along with some clarifications of what it is in comparison to other types of energy, and also includes some examples of different types of renewable energy.
Definition Of Renewable Energy
There’s many slightly different definitions of renewable energy.
Most definitions include the following components … renewable energy:
- Comes from a natural source or natural processes
- Comes from a source, that when used, doesn’t deplete, or can regenerate very quickly (either immediately, or within the course of a human life time)
It is called renewable because, if you compare it to an energy source like fossil fuels, fossil fuels take hundreds or even millions of years to form from the buried remains of decayed plants and animals, that are exposed to heat and pressure over that time. Once mined and used, these sources aren’t renewed quickly. They can eventually present scarcity issues, and issues with depletion of resources.
Modern vs Traditional Renewable Energy
Traditional biomass, such as the burning of wood for heat and energy, is considered a traditional form of renewable energy.
Modern renewable energy is generally all other forms of renewable energy (including modern bio fuel and modern forms of waste-to-biomass conversion).
Different Types Of Renewable Energy (With Examples)
The different types of renewable energy are:
- Solar (PV – photovoltaic, and thermal) – read more about the different types of solar in this guide
- Wind (onshore, and offshore) – read more about the different types of wind in this guide
- Hydropower (run-of-river, storage, pumped-storage) – read more about the different types of hydropower in this guide
- Geothermal (steam, and water)
Read more about the different types of renewable energy in this guide.
Renewable vs Clean/Green vs Alternative Energy
There is a difference between renewable, and green or alternative forms of energy.
Nuclear is an example of an energy source that isn’t renewable (yet), because uranium has be mined to use it. But, nuclear is far cleaner in it’s operation stage (in terms of emissions and pollution) than energy sources like coal and natural gas.
Bioenergy is another example of an energy source that may be renewable in some ways, but, where crops, trees, and other organic matter has to be planted and grown, there are questions over the use of other resources (land, water, fertilizer, pesticide etc.), pollution/emissions, waste produced, and overall how sustainable some methods of bioenergy prodution are.
Read more in this guide about what green energy is.
Alternative energy is usually just an energy form that is different from the conventional energy that is used in a particular sector. For example, an alternative energy car might use renewable energy to power a hydrogen fuel cell car (as compared to a combustion engine car using petroleum or diesel).