Our house is big, detached, and expensive to heat. Mostly single glazed, and built about 100 years ago so no cavity walls. Loft has been extended (not by us) so there are no visible places to add extra insulation.
The previous owners installed 3 (!) gas boilers and a hot water cylinder (megaflow type thing). One boiler does hot water, one does upstairs heating and one does downstairs heating. One boiler is fairly new, one is about 10 years old and the other about 20 years old so likely on its last legs. We also have a cold water tank in the loft which makes me nervous (probably irrationally).
We are wondering if this is now the best system to have but from what we've read about heat pumps our house isn't suitable since it is poorly insulated. Also, the roof isn't in the right orientation for solar panels AFAIK. We are in a conservation area in case that's relevant.
My question is whether there is such a thing as an independent energy advisor who can have a look at our house and advise us on what we can do to be more energy efficient. I am looking for someone who isn't just trying to sell their own particular thing and am willing to pay for good advice. We are based in the SE.