The Basics
Renewable energy in the sense of harnessing the power of nature is by no means a new concept. For centuries, mankind has been doing just that. Renewable energy is energy that comes from resources which are continually replenished such as sunlight, wind, rain, tides, waves and geothermal heat….. natural, clean power.
Using renewable energy allows us to engage in our normal lives without ruining our planet for our children.
Unfortunately, most developed societies currently rely heavily on fossil fuels to create the energy required. These fuels have been created from the decomposition of long buried creatures and plant life that died millions of years ago.
Burning these fossil fuels to give us the energy we need to survive but inevitably leads to a range of pollutions in the air, land and water against which now more and more of the concerned people around the world are now fighting.
These fuels are finite resources which may well not run out in our lifetime but will most certainly become far more expensive to harvest as can be witnessed by the continuing increase of energy prices to householders. The cost problem is exacerbated because developing countries are starting to use fossil fuels much in the way that we have been doing since the Industrial Revolution. So, we have the situation where worldwide demand is rising whilst easy and cheap supply is falling.
The world’s governments have had to consider what to do next and in the main, especially after the Kyoto conference in 2005, they have decided to invest heavily in renewable energy. This means using energy from natural resources that will never run out. Basically the energy is taken from the four natural elements that are considered to make up everything that exists – namely the Light from the Sun (Solar); the movement of air (Wind); the movement of water (Hydro); the heat differential in the air or underground (Air/Ground Source Heating). On top of that is the burning of carbon based material (Biomass) which can be replaced by planting more trees etc..
As none of these sources will run out (at least in our lifetime), the running costs are considerably lower than traditional energy generators. Because these power sources are using natural elements, there is very little waste produced, so they do not pollute the environment.
Wind power has been used to power the sails on boats for a very long time, but we have come a long way since those early designs.
In every civilisation, windmills have been used to turn wheat into flour to provide the most basic food staples.
Water energy has been used for centuries to turn waterwheels that power grindstones for such benefits as turning wheat into flour and in modern times, the hydro-electric dam is an important contributor to the energy needs of many countries.
Power Generation
Global renewable energy capacity additions in 2020 beat earlier estimates and all previous records despite the economic slowdown that resulted from the COVID-19 pandemic. According to data released today by the International Renewable Energy Agency (IRENA) the world added more than 260 gigawatts (GW) of renewable energy capacity, exceeding expansion in 2019 by close to 50 per cent.
IRENA’s annual Renewable Capacity Statistics 2021 shows that renewable energy’s share of all new generating capacity rose considerably for the second year in a row. More than 80 per cent of all new electricity capacity added last year was renewable, with solar and wind accounting for 91 per cent of new renewables.
Transport Fuels
Renewable biofuels have contributed to a significant decline in oil consumption worldwide since 2006. The 93 billion litres of biofuels produced in 2009 displaced the equivalent of an estimated 68 billion litres of gasoline, equal to about 5% of world gasoline production.
Heating
Solar hot water makes an important contribution to renewable heat in many countries, most notably in China, which now has 70% of the global total (180 GWth). Most of these systems are installed on multi-family apartment buildings and meet a portion of the hot water needs of an estimated 50–60 million households in China.
Worldwide, total installed solar water heating systems meet a portion of the water heating needs of over 70 million households. The use of biomass for heating continues to grow as well. In Sweden, national use of biomass energy has surpassed that of oil. Direct geothermal for heating is also growing rapidly.