How many Heatpumps are NOT eligible for the BUS?

The BUS scheme goes live tomorrow morning. Its the ￡5000 heat pump voucher scheme. One of the criteria is that to be eligible the heat pump of choice must achieve a COP of 2.8 in heating mode (there is no limit in hot water) at the design flow temperature.

For people new to heat pumps and who haven't read my book (50 things you need to know about Heatpumps) COP or coefficient of performance is just % efficiency divided by 100. A COP of 2.8 means for every 1 unit of electricity we use, we have to gather 1.8 units from the air in the garden and supply 2.8 units of heat to the house.

If the heat pump is either not on the MCS product register or is less efficient than 280% or doesn't achieve a COP or SCOP of 2.8 as listed on the MCS database it does not qualify so you wont get the voucher.

Now lets imagine I had the time to go on the MCS product database and gather all the cops of every unit, write them down and put them in an excel. I could tell some really interesting stories.

Here is a snippet:

There are 1177 air source heat pumps on the register. Some units cannot run at every temperature, there are some low temp units and some high temp.

If you run your heat pump at a design temperature of 35C, 1166 heat pumps can achieve this but only 1144 of them meet the SCOP of 2.8.

At 45 degrees C, 1149 heat pumps can achieve this temperature and 1121 are eligible for BUS.

and at 50 degrees C, 1112 heat pumps can achieve this temperature and only 1077 will meet the 2.8 SCOP.

There are only 111 heat pumps which can reach 60C of which 25 fail to reach an SCOP of 2.8.

In all cases every unit which fails to hit the target COP has been on the MCS database for more than 5 years.

So we can conclude that any heat pump available today will meet the SCOP target of 2.8 and is eligible to get the BUS. the bar has been set very, very low indeed. No one has been thrown under the BUS.

Now for the fun bit,

Who makes the unit with the highest SCOP?

Who makes the worst SCOP unit?

who hasn't released any new units for eons?

Are heat pumps with the new wonder refrigerant, R290 higher COP than those old R32 units?

What effect does running the unit at 35, 45, 55 and 65 C make on the SCOP and run cost?

Are splits really more efficient than monoblocs?

But I'm a heat pump consultant and that sort of thing isn't free, if I get time I will write a report and sell it on my web site. Don't hold your breath, I'm off on hols later this week.