Heat pump, solar and battery queries (Scotland)

gmc600

Hi,

I've spoken to Homeshield Scotland Ltd about getting a heat pump, solar and battery under the current Scottish grant. Grant for solar has ended but heat pump grant and interest free loan still on offer. The way they have described it it sounds like I'd be mad not to go for it, how much of this is too good to be true? Does anyone that has gone down this route have actual numbers to confirm that their bills are this low? Thanks in advance.

Current electricity usage per year: 1495 kWh at night (1170 of this EV charging) and 1851 kWh during the day.

Current gas usage per year: 10193 kWh

Home was built in 2016 and currently using Mynute i20 20 kW gas boiler for heating and hot water (in combination with 2 solar thermal panels for hot water but this is unmeasured).

Here's what they have told me about what they can offer:

Bills as low as £14/month.

Phase change technology used in combination with the heat pump to avoid changing hot water pipes. Does anyone know what this means? It was described almost like magic so this is the thing I'm most sceptical about! A box which keeps a tank of water at 65°C and requires almost no energy input for 40 year life (surely this can't be true).

No servicing for 25 years (heat pump), only cost would be around £40 for a new fan every 3 years or so.

No maintenance required on solar.

We will avoid paying £17,000+ on gas and electric over the next 10 years (even if prices don't go up).

Reed_Richards

There's a good deal of flim-flam there.

1. You would pay about as much for heat pump running costs as you would with gas if you were on a single rate electricity tariff.  You might be able to save some money by heating your water (or phase change material) on the cheap night-rate tariff.  A really good heat pump system with all-new radiators might might be a bit cheaper to run than gas but I would not count on it.
2. You won't have a tank of hot water.  Instead you will have a tank of a phase change material and you will pass cold water through a coil inside it to get hot water.  This is nothing to do with heat pumps, you could have the same thing with your gas boiler.  The main advantage is that it will store more heat per unit volume than a tank of water; the insulation is good too.  But it undoubtedly requires energy input, you can't make cold water hot without energy.  These are good if you are pushed for space but I think these things go wrong more often than a tank of hot water does.  They're also expensive so hopefully it's not you footing the bill.  One disadvantage is that phase change temperature of the regular material inside is a bit too high to work efficiently with a heat pump.
3. You'll surely void any manufacturer's warranty by not having the heat pump serviced regularly and the maximum length of warranty will not exceed 10 years.  Presumably the installation company relies on going bust before having to honour any warranty obligations.
4. New fan, what new fan?      

FreeBear

gmc600 said: Bills as low as £14/month.

Phase change technology used in combination with the heat pump to avoid changing hot water pipes. Does anyone know what this means? It was described almost like magic so this is the thing I'm most sceptical about! A box which keeps a tank of water at 65°C and requires almost no energy input for 40 year life (surely this can't be true).

Well... Last month, my gas bill was only £9 - Just 54p for gas, the rest was standing charges. Electricity was quite a bit higher at £45, and there isn't much scope to get it any lower. £14 per month just about covers standing charges depending on the tariff you are on.

Phase change technology - Is this being used to boost the temperature of the water so that you can use microbore pipes in the central heating system ?

DougMLancs

As others have said, your costs can be pretty low with ASHP+PV+battery (my annual energy bill is actually negative now) but not necessarily for the reasons they’re saying (which sound like a load of half truths and sales pitch). 

I would try Barry Sharp at Renewable Heat or IMS Heat Pumps (who also offer solar PV and a finance package since their recent partnership with Homeserve if that’s what you need). 

Reed_Richards

Lots of hard sell here but these are the phase change material people: https://sunamp.com/en-gb/