To give you an indication of costs: we offer PV installs for 12 panels or more, this starts from £7k. If you want to add a battery that would start at £10k (for PV and battery). Standard heat pumps installations start from £15k: depending on your current heating system some replacement of radiators may be required in addition. Installation of heat pumps for larger houses start from £18k. Whole house assessment reports start from £1500+VAT.