This looks good - speaking as a non-expert in heat pumps
https://www.theengineer.co.uk/content/n ... -heat-pump
Octopus heat pump
Octopus heat pump
Solar PV since July '22:
5.6kWp east/west facing
3.6kW Sunsynk hybrid inverter
2x 5.12kWh Sunsynk batteries
0.8kWp Hoymiles East facing on the man cave (further 0.8kWp to be added west facing)
Ripple DW 2kW
5.6kWp east/west facing
3.6kW Sunsynk hybrid inverter
2x 5.12kWh Sunsynk batteries
0.8kWp Hoymiles East facing on the man cave (further 0.8kWp to be added west facing)
Ripple DW 2kW
Re: Octopus heat pump
Anyone know if the COP of a high temp HP is lower than that of a normal HP, when only heating the radiator water to ~35C/40C?
I'm just wondering, as we have all microbore, so hard to get an ASHP approved. But as we only consume about 6,000kWh of gas pa, and have two A2A units as back up, I'm thinking a high temp unit, would tick any necessary boxes for approval, grant etc. but still provide the heat we need for 95%-99% of the time, at a 'normal' HP temp.
I'm just wondering, as we have all microbore, so hard to get an ASHP approved. But as we only consume about 6,000kWh of gas pa, and have two A2A units as back up, I'm thinking a high temp unit, would tick any necessary boxes for approval, grant etc. but still provide the heat we need for 95%-99% of the time, at a 'normal' HP temp.
3.58kWp ESE PV + 2.0kWp WNW PV.
Two BEV's.
Two small A2A heatpumps.
Two BEV's.
Two small A2A heatpumps.
Re: Octopus heat pump
https://www.theecoexperts.co.uk/heat-pu ... heat-pumpsMart wrote: ↑Fri Sep 15, 2023 2:04 pm Anyone know if the COP of a high temp HP is lower than that of a normal HP, when only heating the radiator water to ~35C/40C?
I'm just wondering, as we have all microbore, so hard to get an ASHP approved. But as we only consume about 6,000kWh of gas pa, and have two A2A units as back up, I'm thinking a high temp unit, would tick any necessary boxes for approval, grant etc. but still provide the heat we need for 95%-99% of the time, at a 'normal' HP temp.
"Is it worth getting a high temperature heat pump?
It's not worth getting a high temperature heat pump, in most cases.
They typically cost 25% more to buy and install than regular heat pumps, they're around 20% more expensive to run, and they won't cut your carbon footprint by as much.
You should usually only buy a high temperature heat pump for a property that's large, extremely hard to insulate, and requires a high amount of hot water.
If your building is listed, or if it's too old for energy efficiency improvements to be a realistic prospect (either financially or practically), a high temperature heat pump may be your best bet.
Otherwise, we'd almost always recommend insulating your home and buying a regular heat pump."
15.2kW PV > 100MWh generated
Ripple 6.6kW Wind + 4.5kW PV > 18MWh generated
5 Other RE Coop's
105kWh EV storage
60kWh Home battery storage
40kWh Thermal storage
GSHP + A2A HP's
Rain water use > 490 m3
Ripple 6.6kW Wind + 4.5kW PV > 18MWh generated
5 Other RE Coop's
105kWh EV storage
60kWh Home battery storage
40kWh Thermal storage
GSHP + A2A HP's
Rain water use > 490 m3
Re: Octopus heat pump
Mart, I've been looking at Vaillant heat pumps as a possible replacement for my oil boiler and it says that they can output water up to 75C.
But for EN14511 testing it only gives figures up to 65C, the COP's (all at 7C outdoor air temperature) are as follows:
Water 35C - 5.30
Water 45C - 4.10
Water 55C - 3.10
Water 65C - 2.30
The COP of 5.30 is one of the highest I have seen for any domestic ASHP.
3.87kWp PV
10.24kWp PV SolarEdge system
Tesla Powerwall 2
100 x 47mm elsewhere tubes (still being installed!) Now likely to be removed for more PV.
MK2 PV router DHW diverter
Morso 5kW WBS
Vaillant AroTherm 10kW ASHP
Nissan Leaf
10.24kWp PV SolarEdge system
Tesla Powerwall 2
100 x 47mm elsewhere tubes (still being installed!) Now likely to be removed for more PV.
MK2 PV router DHW diverter
Morso 5kW WBS
Vaillant AroTherm 10kW ASHP
Nissan Leaf
Re: Octopus heat pump
Thanks guys, just pondering options. Last winter I ran the combi at it's lowest radiator temp to see how that faired, just as a guide. It was OK for all but 2 weeks. However, it wasn't on 24/7, so maybe not the fairest comparison.
BTW that 6,000kWh figure for gas includes oven and DHW, which seems to be around 100kWh/month in non-heating months.
BTW that 6,000kWh figure for gas includes oven and DHW, which seems to be around 100kWh/month in non-heating months.
3.58kWp ESE PV + 2.0kWp WNW PV.
Two BEV's.
Two small A2A heatpumps.
Two BEV's.
Two small A2A heatpumps.
Re: Octopus heat pump
When they say "can output water up to 75C", what they mean is the internal gas temp can get up to 75 degrees before the unit trips out. So if you have a ludicrous high flow rate the output water may theoretically get to that temp, but in practise there will be a temp difference between the gas temp and the output water temp, circa 2 to 5 degrees.
15.2kW PV > 100MWh generated
Ripple 6.6kW Wind + 4.5kW PV > 18MWh generated
5 Other RE Coop's
105kWh EV storage
60kWh Home battery storage
40kWh Thermal storage
GSHP + A2A HP's
Rain water use > 490 m3
Ripple 6.6kW Wind + 4.5kW PV > 18MWh generated
5 Other RE Coop's
105kWh EV storage
60kWh Home battery storage
40kWh Thermal storage
GSHP + A2A HP's
Rain water use > 490 m3
Re: Octopus heat pump
Octopus acquired RED and their secret sauce was a technology to inject gas into the exchanger to cool it down when in high temp mode. They also have a secondary exchanger for low temp operations.
Samsung's propane unit also does this.
They will fight the MCS on the ideal pump velocity for this system, I think octopus will try to bump it to 1.5.
As I have said many times before your local one man "
Gas engineer" is now a dodo and large capital intensive businesses can afford to stomp them out and tie customer install performance to the money/grant.
Samsung's propane unit also does this.
They will fight the MCS on the ideal pump velocity for this system, I think octopus will try to bump it to 1.5.
As I have said many times before your local one man "
Gas engineer" is now a dodo and large capital intensive businesses can afford to stomp them out and tie customer install performance to the money/grant.