For the last few weeks I’ve been reviewing all the different renewable energy technologies that are available to us, focussing particularly on wind turbines, solar hot water and solar photovoltaic systems. A summary of what I’ve found out is given in the table below.

After discussing this with the rest of the management team here, we’ve decided that the system that is best for our site is the solar thermal system that will provide hot water for the factory. We discounted wind turbines because we were advised that our roof is not really suitable for mounting turbines and the average wind speeds in our location are very low so we would not generate much power. Solar photovoltaics are just too expensive at the moment and have a very long payback even if we did manage to get a grant from the DTI’s Low Carbon Building Programme. At the moment, all our hot water is provided by an electric emersion heater so installing a solar thermal system will reduce the amount of electricity that we use on site, thus reducing our energy bills all year round. Although the savings will not be massive because we don’t have a big hot water demand, there’s a potential 4% return on our investment, which isn’t too bad. And if we are successful in getting a DTI grant, that will increase to an 8% return which is actually pretty good. More on this when I’ve had some detailed quotes back from solar panel installers.