Every year, each square metre of the UK receives between 900 and 1200 kWh of solar radiation. Capturing just some of this energy could make a significant contribution to fulfilling our energy requirements.
There is much talk of the possibility of a future ‘hydrogen economy’, which will power all our vehicles and homes. It is important to remember that hydrogen is not an energy source; it is an energy carrier. To obtain hydrogen it must be split from either natural gas or water molecules. The former, most widely used, method not only requires energy but also gives off carbon dioxide (CO2) in the process. Hydrogen produced in this way requires more energy to make than will eventually be returned when it is used. It makes more sense from a climate perspective to burn the natural gas itself than to convert and re-convert it to hydrogen in this way.
Even among green campaigners, nuclear energy is quietly gaining ground as a potential solution to the impending energy crisis. However several issues – particularly those of raw materials, cost and waste – remain unaddressed within the mainstream of opinion.
Each year, UK livestock produce some 60 million tonnes of collectable faeces. If left to run into water-courses or even spread on fields, this waste can lead to the same problems associated with excessive fertiliser use – algal blooms and aquatic life starved of oxygen.