60 second guide to... Solar energy
Harnessing solar power has gained widespread popularity over the past few years. Here’s why people are getting interested in solar
All of our energy ultimately comes from the sun. The sun drives the weather systems that turn wind turbines and the water cycle, which powers hydroelectric stations. Even oil, coal and gas are the remains of plants that grew thanks to photosynthesis.
But when people talk about “solar energy they’re usually referring to technologies that allow us to generate power directly from the sun’s rays.
These technologies fall into two categories: solar photovoltaic, for generating electricity and thermal solar, for generating heat.
Solar photovoltaic
Photovoltaic solar panels – or PV panels for short – convert sunlight directly into electricity. Each panel consists of many individual “cells”, each of which contains a semiconductor material that generates an electric flow when struck by solar rays.
The semiconductors used in most solar panels are based on silicon – the same substance that sand and glass are made of.
PV panels are most commonly located on the roofs of individual buildings such as homes and offices. The typical installation cost for domestic systems is around £10,000–15,000, but a solar roof could still be a sensible investment depending on a number of factors. These include: panel lifespan, the future price of other energy sources, and how much electricity you consume in the daytime (when the panel is working).
Thermal solar
Thermal solar panels, also known as solar “collectors”, work entirely differently from photovoltaic panels. Instead of creating a flow of electrons, they capture the warmth of sunlight and use it to heat water.
On a domestic level, thermal solar generates hot water that can be topped up with a regular boiler or electric heating element as required. A typical installation costs around £4000 and cuts household emissions by around 8 per cent.
On a bigger scale, thermal solar can be used to create power plants in hot countries. Arrays of huge mirrors known as “concentrators” direct large amounts of sunlight onto a small area, boiling a fluid and generating electricity.
Solar futures
Solar technology currently provides only a tiny fraction of the world’s electricity and heating energy, but that looks set to change over the coming decades.
As the panels get cheaper and less energy-intensive to produce they should become more affordable, as well as more environmentally beneficial.
Team Green Britain and London Organising Committee of the Olympic Games and Paralympic Games Ltd (LOCOG) do not endorse any of the products, companies, organisations, opinions or websites that have been mentioned in this article. The content of this article has merely been provided as background to, or discussion on, various topical issues relating to the environment and it is not necessarily representative of the views of Team Green Britain and LOCOG. Further, any figures and calculations noted in this article are estimates (unless otherwise specified), and may vary in light of numerous factors and readers are advised to undertake their own research in relation to the facts and figures applicable to their particular circumstance.