What is renewable energy?
Renewable energy is best described as “naturally recurring energy flows which are replenished at the same rate as they are used”.
Most sources of renewable energy are derived principally from the enormous power of the sun’s radiation, whether it be direct solar radiation or stored solar energy in the form of windpower, hydropower, biomass, or ground heat. These are at once the most ancient and the most modern forms of energy used by mankind.
More modern technology also allows the collection of energy from the tides, underwater currents and heat from the earth’s core in the form of geothermal energy.
Why use Renewable Energy?
The rapidly increasing popularity of renewable energy technologies is driven by two fundamental motivations. - financial and environmental.
Financial Motivations
Fossil fuels are a finite resource and it is generally accepted that cheap oil and gas will run out in our lifetime.
As with any commodity, when demand outstrips supply the market price is forced upwards. As natural resources of fossil fuels continue to be depleted, so prices will rise with increasing speed. We have already witnessed the early stages of this process, and there is nothing to suggest that the trend can be reversed.
Renewable energy is free, and its supply is only limited by our own desire to utilise it.
Modern technology is reliable, cost effective, and allows the harvesting of free, limitless and future-proof energy. Huge cost savings are available for those with the foresight to take advantage.
Environmental Motivations
Climate change has emerged as the greatest threat to modern society.
Despite decades of research, there are many important issues that remain uncertain. However, much has been established beyond reasonable doubt, and the basic mechanics of climate change are well understood.
The world is warming, with much of it due to human emissions of greenhouse gasses, in particular carbon dioxide, which is produced when fossil fuels (coal, oil and gas) are burned to generate energy . Since the industrial revolution began some 200 years ago, the developed world has been burning fossil fuels in earnest, and the concentration of greenhouse gases in our atmosphere has increased dramatically. The result is that the Earth’s temperature has increased more rapidly in a shorter period of time than it has for thousands of years.
Seemingly small changes in surface temperatures have a dramatic impact on the earth’s delicate eco-system. Weather patterns are becoming increasingly disrupted and unpredictable, and our winters are warmer with heavier bursts of rain leading to flash floods. Summers are now longer and warmer with widespread water shortages.
By the end of the century, the average temperature in the UK could be between 1°c and 4.5°c hotter than today, depending on how the issue of climate change is managed. Although the precise long term effects of climate change are impossible to predict, our children and grandchildren are certain to face intense heatwaves and greater threat from wildfires. As the summers become hotter and drier, drought will be accompanied by water shortages, building subsidence, withered crops and diseased trees. Severe storms and rising sea levels will eat away at our coastline and low lying areas, the animal and plant worlds will be thrown into turmoil, and effects on health could also be profound.
Around 26% of emissions come from the energy we use to heat, light and power our homes. By reducing our personal emissions, we can all play an important part in the fight against climate change.