EPCs and energy usage

StewartR

StewartR

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I'm looking at a commercial property which I might rent. Trouble is, I'm concerned that it might be hugely expensive to heat, and I want to get some sort of estimate of the likely cost.

The estate agent can't/won't help. Not interested.
The landlord can't/won't help. Not their business.
The previous tenants could help, but the estate agent won't put me in touch with them because GDPR.
So I think I'm pretty much on my own.

I know the floor area and I know the EPC rating. Does that give me any way to estimate the likely energy usage for heating? It doesn't need to be very accurate at all - I just want to get a feel for whether it's going to be around £1k per year, £5k per year, £10k per year, or whatever.
 
Do you know anyone who has a similar size building who you could base this on?
 
gerry s said:
What sort of property, size,use, heat source?
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Detached brick-built single storey, probably built 1940s-1960s?, with a pitched tiled roof and 24 (!!!) single-glazed (!!!!!) windows. No info on whether there is cavity wall insulation. No info on how much - if any - insulation might be above the suspended ceiling. Roughly 2000 sq ft. Open plan office space. Electric panel heaters on the walls, not sure of the exact model or functionality - might be instantaneous heat, might be storage heaters - but they don't look terribly new.
 
StewartR said:
The previous tenants could help, but the estate agent won't put me in touch with them because GDPR.
Click to expand...


They could pass your enquiry on to the previous tenants.
 
Uninsulated brick cavity
Uninsulated pitched roof
Assuming 2.8mtr ceilings
Single glazed windows
38/40 kw

Insulated brick cavity
100mm insulated pitched roof
Assuming 2.8mtr ceiling
Double glazed windows (or secondary double glazing)
18/20 kw
800-1600 gas pa
2000-4000 electric pa

This assumes a decent level of heating but there are many many variables so can only be a guide. Hope this helps
 
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gerry s said:
Uninsulated brick cavity
Uninsulated pitched roof
Assuming 2.8mtr ceilings
Single glazed windows
38/40 kw

Insulated brick cavity
100mm insulated pitched roof
Assuming 2.8mtr ceiling
Double glazed windows (or secondary double glazing)
18/20 kw
800-1600 gas pa
2000-4000 electric pa

This assumes a decent level of heating but there are many many variables so can only be a guide. Hope this helps
Click to expand...
That's really helpful, thanks.

Just one minor question though - the way you've laid that out, with one set of prices in the same block of text as the second set of specifications, is a little ambiguous. Does the range of costs (ie 2000-4000 electric pa, etc) cover the range from the first spec (low insulation) to the second spec (high insulation)? Or does it just apply to the second spec, with the costs for the first spec presumably being considerably higher?
 
Worse case scenario gas up to £1600 electricity up to £4000
Best case scenario gas from £800 plus and electricity from £2000
If it’s worse case and you just fitted 100mm of loft insulation you would reduce heat loss by about 30%
 
Get your MPAN number.
Contact an energy supplier and ask them to quote.
They may give you details of current supplier who will have a record of usage.
Easiest way I can think of....
 
JonathanRyan said:
EPCs for domestic properties have an estimated heating cost for 3 years on them - hopefully it's the same for commercial. The figures they use are nonsense but you can compare with (say) your own home and get a multiplier. You can get a copy of the full EPC rather than the tiny version estate agents like here

https://www.epcregister.com/reportSearchAddressByPostcode.html
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Thanks Jonathan. You've reminded me that I had actually retrieved the EPC for this property - hence the title for this thread - but I forgot to mention what it says.

There are actually two different EPC registers. The one for non domestic properties is here:
https://www.ndepcregister.com/reportSearchAddressByPostcode.html

Non domestic EPCs are confusingly different from domestic ones. They use a scale of A+ to G, but the underlying numbers are completely different: for non domestic ones a low number is good, whereas for domestic ones a high number is good. Unfortunately I can't find anything on the internet that tells me whether the numbers have any kind of actual units associated with them - if low is good, you might think the number is directly related to energy usage, but I don't know.

Anyway the EPC rating for the property of interest is 98 - just scraping into the D band.

@gerry s - Where does that fit into your best case / worst case spectrum?

At the bottom of the EPC certificate there is some "technical information", which includes annual CO2 emission rate and annual primary energy usage. The CO2 emissions are 86.95kg per sq m per year, but unfortunately the primary energy usage is "Not available". (I love that spurious accuracy. 86.95, not 86.94 or 86.96. Yeah, right.)

Since the heating is 100% electric, I expect the CO2 figure will be based on the average emissions for the UK electricity generating industry, or at least what the average was in 2015 when the EPC was produced. It's hard to get definitive data on this but it looks like about 400g of CO2 per kWh. So 86.95kg per sq m per year, times 168 sq m, comes to 14,600 kg per year for the whole property. At 400g per kWh that's 36,500 kWh per year. At 17p per kWh (the current Ofgem price cap) that's £6200 per year. Ouch.

@gerry s - I've managed to come up with a number which is 50% higher than your worst case estimate. Presumably the figure of 400g CO2 per kWh is wrong, or at least not consistent with the assumptions which were made when the EPC was created. Any views on this?
 
Meeten said:
Get your MPAN number.
Contact an energy supplier and ask them to quote.
They may give you details of current supplier who will have a record of usage.
Easiest way I can think of....
Click to expand...
It's not *my* MPAN number, unfortunately. I could ask the estate agent but I doubt they would know. So I'd have to go back over there with the estate agent for a quick look at the meter. Possible, but not entirely hassle free.

I'd be amazed if an energy supplier would give me details of a different customer's usage. Do you really think they would?
 
StewartR said:
It's not *my* MPAN number, unfortunately. I could ask the estate agent but I doubt they would know. So I'd have to go back over there with the estate agent for a quick look at the meter. Possible, but not entirely hassle free.

I'd be amazed if an energy supplier would give me details of a different customer's usage. Do you really think they would?
Click to expand...
That might give an indication of average usage, without being specific. Worth a try.
 
My worse case was 38000 kw@11.5p= £4370 pa. didn’t think you would want the highest rate. Although just quickly and the lowest I could find was 11.9p I was looking for the worse case at the best price although I did actually put 38/40kw and not 38000/40000kw
 
gerry s said:
My worse case was 38000 kw@11.5p= £4370 pa. didn’t think you would want the highest rate. Although just quickly and the lowest I could find was 11.9p I was looking for the worse case at the best price although I did actually put 38/40kw and not 38000/40000kw
Click to expand...
Thanks very much. You estimated 38-40,000 kWh and I came up with 36,500 kWh using a different approach, so it's very reassuring that we're in the same ball-park - that's certainly good enough for my purposes at present. You assumed 11.5 p/kWh and I assumed 17 p/kWh, which is the main difference between our cost estimates, and I can nail that one just by asking for quotes from potential suppliers. Great stuff. I feel like I've moved a step forward.
 
Don’t forget you can make a 30/35% saving on that just by putting 100mm of loft insulation. Best of luck with it anyway.
 
gerry s said:
My worse case was 38000 kw@11.5p= £4370 pa. didn’t think you would want the highest rate. Although just quickly and the lowest I could find was 11.9p I was looking for the worse case at the best price although I did actually put 38/40kw and not 38000/40000kw
Click to expand...

If you are paying 17p/kWh then you are being taken for a ride.
Unless you are a high peak time user AND you are going through a consultant, then I cannot see any reason the cost should be as high as that.
Note that if you go via a consultant, they add on their commission to the bill and the supplier sends it out to the customer wrapped up in the unit rate.
Typical fees are 2p/kWh for NHH supplies, but in some cases it can be as high as 5-7p/kWh.

Wholesale electric markets have seem a tremendous rise from Aug 2018, but the mild winter has seen them retrace, so there is value to be had. (not advice, I'm not telling you to fix your supplies), but current prices are considerably lower than they were 3, 6, 9 months ago.

11.5 - 12p is about right.
Prices for longer dated periods are marginally lower, so a 24m deal could work out better than a 12m deal......
 
Meeten said:
If you are paying 17p/kWh then you are being taken for a ride..... 11.5 - 12p is about right.

Prices for longer dated periods are marginally lower, so a 24m deal could work out better than a 12m deal......
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I'm not paying 17p. I'm not paying anything yet; I'm just at the stage of considering whether to rent the property. I used 17p in my estimate because that's the Ofgem cap for variable rate tariffs in the domestic market, and I know nothing about the business energy market, so 17p is a sort of worst case for planning and budgeting purposes. My domestic tariff is 15p, so it's good to know that there is potential to improve on that.

Though I'm really surprised by your assertion that 11.5-12p is about right. There are no domestic tariffs that are that low at present. Is there some persistence structural difference between the domestic and small-user commercial markets?
 
I can't help with any of the technical stuff but I'm assuming you have googled the address to see if it throws up any previous companies/occupants?
 
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StewartR said:
I'm not paying 17p. I'm not paying anything yet; I'm just at the stage of considering whether to rent the property. I used 17p in my estimate because that's the Ofgem cap for variable rate tariffs in the domestic market, and I know nothing about the business energy market, so 17p is a sort of worst case for planning and budgeting purposes. My domestic tariff is 15p, so it's good to know that there is potential to improve on that.

Though I'm really surprised by your assertion that 11.5-12p is about right. There are no domestic tariffs that are that low at present. Is there some persistence structural difference between the domestic and small-user commercial markets?
Click to expand...

The B2B market is different to the domestic.
There is a greater linkage to the current wholesale market and forecasts of Non Commodity costs.
In the domestic market these have to be forecast for a longer time period.

Either way, I would suggest that using 12p/kWh is about the right level for your plans on rental costs.

Regards

Meeten
 
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