Powering an ASHP

Hi there
Half way through my new build and looking at getting power to the site.

I have an 8kW air source heat pump and a 4 bed house to power.

At the moment I have 4kW of solar panels being installed. I take it this will not be enough to power the ASHP.

I also have a power supply to the farm shed behind the house but it has experienced a voltage drop over the run of the cable from the mains connection 200 metres away.

The electric company want £15k to connect the house to the transformer and run cable underground to give me power.

What other alternatives do I have with all of the above taken into account.

Can I somehow reverse the voltage drop at the shed to make use of the power there.

Can solar power a heat pump with say the help of battery back ups.

Are on demand generators any good.

Could I install a battery bank that charged from the shed and has enough power to start the ASHP.

I think the ASHP needs a fair voltage to start it up every time it kicks in.

Many thanks