Power sources

We have a planning requirement that 10% of the energy needs to come from renewable sources. Sounds simple but it is amazing how little even the experts know about how to do this. Maybe most people just dont bother and maybe the planning departments never actually check. Howeber, the last thing you want is a problem at the late stage of a build so I did a lot of research up front and talked to different people. The best option would have been a ground source heat pump and we even made the utility room bigger to accomodate this. However there was not enough ground outside for the ground loops which would mean digging deep bore holes which would have been very costly. The cost of this virtually ruled out this option. So we decided on an air source heat pump. The main downside of these is that they might be noisy and they also produce less power than ground source. However we are assured they will be sufficient to generate 10% and the company providing them will write an energy statement to support this. Solar panels by themselves would probably not be sufficient but we have the option of using them as a top up if required. These can be costly but can be added at a late stage in the build if required. We are very tempted by having a ventilation system for heating and cooling but it will add quite a bit to the build cost and we have to see if we can fit it into the budget.