Updated EPC's and GDAR's - Is DECC trying to kill the Domestic RHI before it starts?

[Worcester]

We are having a few challenges with the energy assesment values for Domestic RHI properties - any one seen this yet.

5 Properties, all run through the full MCS Energy and Heat Loss calcs,
same 5 properties, EPC's using the RdSAP all give an energy requirement between 30 and 50% lower than the MCS calcs,

So which is right?

Based on actual consumption figures and old epc's done on some of the properties the MCS one is within 10%

The problem is that the RHI is based on the EPC figure.

So we have one property estimated to consume 47,000kWh a year yet the EPC says and therefore the RHI will only pay for 34,000kWh ..

Seems like we're not the only ones to be facing this challenge:
EPC Problems could wreck domestic RHI

the MCS MIS Document says "The Standard Assessment Procedure for dwellings is not designed to accurately determine the heating and domestic hot water energy requirements of real dwellings."

In a slight understatement even DECC publicly said : "We know RdSAP isn’t the most accurate way of estimating annual heating and hot water requirements"

With the RHI figure significantly below historic consumption levels, we are having difficulty achieving a +ve ROI , so some type of Renewable Energy just won't get a look in through the RHI, or the installtion owener will be significantly under-compensated - maybe that's DECC's idea? - Kill it off before it starts?

 

[jason121]

Re: Updated EPC's and GDAR's - Is DECC trying to kill the Domestic RHI before it star

I have heard of this. Apparently there is an equation on the DECC web site that, when applied, will drop the KWhrs of the MCS installers design figures.

 

[Greenday]

Re: Updated EPC's and GDAR's - Is DECC trying to kill the Domestic RHI before it star

I have heard of this. Apparently there is an equation on the DECC web site that, when applied, will drop the KWhrs of the MCS installers design figures.

The equation is as follows for a heat pump

kwh from EPC x (1- 1/SPF) = kwh x.073 pence

example. 25,000 x(1-1/2.5)= 15,000 x 7.3p = £1050 rhi payment per annum

1050 x 7 years = £7350 total RHI payment minus the RHPP if you claimed it.

 

[jason121]

Re: Updated EPC's and GDAR's - Is DECC trying to kill the Domestic RHI before it star

I was told minimum SPF is 2.5 so all High temp heat pumps wont qualify for RHI. Can anyone confirm this.

 

[Greenday]

Re: Updated EPC's and GDAR's - Is DECC trying to kill the Domestic RHI before it star

I was told minimum SPF is 2.5 so all High temp heat pumps wont qualify for RHI. Can anyone confirm this.

Thats correct no HT pump will qualify for RHI.

A rad circuit running at 50 degrees should be about 2.7 SPF

 

[TedM]

Re: Updated EPC's and GDAR's - Is DECC trying to kill the Domestic RHI before it star

Legacy systems will be deemed at a SPF of 2.5 so an existing install, that fully complied with whatever version of the MCS standard existed at the time of installation, should be eligible irrespective of the actual SPF.

It's not clear exactly when the cut-off date for this allowance is, so it may apply up to the point when RHI actually goes live or it may be cut-off at the publishing date for the MCS Heat Emitter Guide or DECC may find another reason to apply a different date.

 

[Worcester]

Re: Updated EPC's and GDAR's - Is DECC trying to kill the Domestic RHI before it star

@Greenday 2 points
1) You are correct with what is paid as renewable energy, however that still isn't the issue as the start point - the EPC kWh taken - bears little resemblance to real kWh based on fuel bills for two years, or the MCS calculation.
2) the SPF comes from the emmiter guide published by MCS so for a flow temperature of 50°C, you use an ASHP SPF of 2.7 and for a flow temperature of 45°C you use an ASHP SPF of 3.0 - Net effect anything over 60° flow doesn't have an SPF so wont qualify for RHI (i.e. the high temp ASHP's) so at SPF 3.0 the for every 3 kWh of heat provided / used you get paid for 2 (the renewable element) at 7.2p/unit. or equivalent to 4.87p for all the heat.

In a retrofit environment (not refurb) a flow temperature of 45 is practically the lowest you can go as the radiators will need to be (from the guide) 3.1 times larger than "normal" - this can be achieved using high efficiency or fan assisted rads without major disruption to the property. (1 -1 replacement, very similar size)

I would be surprised if you could retrofit a quality heat pump, change / add a hot water cylinder, and change all the radiators, and still make sensible money for £7350 including VAT.

I had discussion tady with a large number of ASHP manufacturers, and all the quality AS Heat Pump providers bar none are lobbying DECC to get a proper SPF figure, based on actual certified results, used for the RHI calculations. - We'll see how that goes.

Rest of reply moved to Sun Lounge ....

 

[Greenday]

Re: Updated EPC's and GDAR's - Is DECC trying to kill the Domestic RHI before it star

Worcester I broadly agree with all you have said although I'm not privy to what you posted in the Sun Lounge as they won't let me in!

I was doing a GDAR today for the client to claim the RHPP and the kwh on the EPC came out considerably higher than the Ecodan calculation!

Interestingly Mitsubishi claim an SPF of 3.5 for a radiator circuit.

The only thing I would add to your post would be the savings the client will make switching off oil.

The 15000kwh used in my example was a random figure and I agree the total RHI generated wouldn't pay for a Heat Pump upgrade.

Now if that figure was 35,000kWh the RHI benefit would be more interesting.

 

[The Solar King]

Re: Updated EPC's and GDAR's - Is DECC trying to kill the Domestic RHI before it star

I know for ST, the calculation of renewable heat input departs from SAP in several respects. A lot of this is still being worked out. This may also affect other technologies.

I too have heard that things as they stand do not look that good for ASHPs.