Solar electric fence energisers are undoubtedly the way of the future, and are becoming increasingly popular in the UK. They are reliable, robust and very user friendly. There is usually a rechargeable deep cycle battery inside the unit, and the solar panel recharges the battery for you. Just like with your mobile phone, after some time you will eventually need to replace the internal battery but this is easily done. Solar energisers are cost effective and very easy to use.