Air Source Heat Pump Quote

[c13pep]

The second quote looks promising with the extra HW  but the difference between the two units is 3.5 Kw so is the second unit less efficient. I don`t know about the LG unit but would expect its efficiency to be close to the Mitsubishi unit so why the increase, the only thing that comes to  mind is that less radiators are being changed for the LG so maybe it`s the pipework and rads that are less efficient. Based on my own installation then only the bathroom and cloakroom radiators were left unchanged.

Whoever you employ I cannot emphasise enough the importance of `SETTING UP` the system correctly to your criteria, so, if possible, check out their reviews and don`t be afraid to ask for proof of previous installations and try and speak to these people.  It`s a very large financial commitment (well is was for me) so getting it right first time is the `name of the game`. My system was correctly installed but set up proved to be a problem before Mitsubishi stepped in to make the final tweaks, bearing in mind that my main contractor also ran a training school for ASHP installers accredited by Ecodan

My system is currently maintained by a company whose chief engineer has exactly the same installation as mine, he is young, very tech savvy and definitely knows the system inside out along with the knowledge to make positive adjustments

 

CHRIS P

. 

[Temp]

On 05/02/2020 at 13:24, Benrh said:

first quote of £15k includes a Ecodan 8.5kw pump and 170 litre tank plus replacement of 13 rads. Estimate of £775 electricity bill

 

second quote of £13800 was for LG R32 Therma-V 12kw Monobloc plus a 250L Horizontal Unvented cylinder plus replacement of 9 rads. Estimate of £840 electricity bill

 

On 24/01/2020 at 20:28, Benrh said:

Only guide I can give is around £1200+ pa oil bill.

 

So they are predicting a considerable % saving. 

 

What tariff were they using to calculate your likely electricity bill?  This site is one of the few that compares different fuels systems but its not without fault...

 

https://nottenergy.com/resources/energy-cost-comparison/

 

They estimate:

 

Pence per kWh (after boiler efficiency)

 

Electricity 20 p/kwh

Oil/Kerosene 5.73 p/kWh

ASHP 7.81 p/kWh

 

Their figure for Electricity appears to be too high. I think 15 p/kWh is more reasonable than 20p/kWH. 

 

If they used 20p electricity in their ASHP calculation the figure for ASHP should be nearer 7.8 * 15/20 = 5.8p /KWH but that's still about the same as oil (5.7p/kWh).

 

Ok so the Notts web site have assumed oil boilers are 90% efficient, and yours probably isn't, that appears to be where the saving is coming from.

 

[SteamyTea]

13 minutes ago, Temp said:

Their figure for Electricity appears to be too high. I think 15 p/kWh is more reasonable than 20p/kWH. 

 

Not bothered to look at the Notts site for years, but does the 20p/kWh include meter rental and taxes?

Or a blend of day and night rate (which is tricky as you need a split).

It may also reflect standard rates, rather than one off introductory offers.

It is really quite easy to go to Google and find out what prices are being charged by the big 5.

[Temp]

All they say is...

 

"Electricity: Based on an average of the 6 major electricity suppliers’ online prepayment, credit and direct debit tariffs, including standing charges and VAT, but not Economy 7.  Data used are the Tariff Comparison Rates (TCR) provided on the 6 major energy suppliers’ website."

 

[Temp]

If i was to switch today the best rates for my consumption would be are around 13p/kWh but I'm paying a bit more than that as I switched less than a year ago.

 

That would make the ASHP figure 7.8*13/20 = 5.07 p/kWh just a bit cheaper than oil. 

 

They are suggesting bills would reduce from £1200+ to £840 about a 30% reduction. Still find that hard to believe.

Edited February 7, 2020 by Temp

[DamonHD]

Moving to (say) Octopus Agile and simply avoiding running the ASHP from 4pm to 7pm (eg coasting on the house thermal capacitance for space heat) your electricity would cost ~10p/kWh.

 

Rgds

 

Damon

[SteamyTea]

3 hours ago, DamonHD said:

4pm to 7pm

When I am at work.

I am still worried about these 'challenger' companies.

How can they do it so cheap compared to the big boys.

[Jeremy Harris]

34 minutes ago, SteamyTea said:

When I am at work.

I am still worried about these 'challenger' companies.

How can they do it so cheap compared to the big boys.

 

 

I'm pretty sure, from watching the rates, that what's happening at the moment isn't profitable.  These smaller suppliers are working on very tight margins and relying on continued fast growth in their customer base to survive (hence the attractive referral incentives they are offering - they need to grow their customer base to survive).  I have a sneaking suspicion that their business model is a bit like a pyramid scheme, that may well just fail at any time.  The track record for smaller, more innovative, energy suppliers is not at all good, many have gone to the wall in the past couple of years.

 

The biggest problem that they will face when more of their competitors jump on to the flexible pricing bandwagon is that consumers will find it harder and harder to compare tariffs.  This is already clear with the big comparison sites, as they are unable to fairly compare the flexible ToU tariffs with the offerings from other suppliers.  I've been tracking both Go and Agile against our Bulb Varifair E7 tariff, and so far both Go and Agile are significantly more costly, even in winter, when we buy more electricity than at any other time of the year.  This comparison is only possible because I have an accurate (6 minute sampling period) record of our actual energy consumption.  Anyone who doesn't have accurate data to at least half hourly sampling just is not going to be able to compare tariffs at all easily.

[redtop]

On 29/01/2020 at 19:52, c13pep said:

My house is 6 bed semi (1960s) with 22 radiators which was converted from LPG to ASHP 5 years ago with great success after a shaky start.

My own installation was obviously retro fitted with the radiators being, in the main, replaced for `doubles` after being worked out by the plumber.

My criteria was specific in that the main rooms had to be capable of reaching 25 degrees due to my wife's ongoing health problems 

The system had to generate enough hot water to supply 2 bathrooms, 1 ensuite, 1 cloakroom and the kitchen

Resulting system was Ecodan 14 Kw outside unit, matching Hydrobox in roof space plus 300L HW tank also in roof

The system is run as a `normal` boiler would run switching off at night but on all day

The HW temperature is set at 42 - 52 degrees which is very hot without being scalding 

We encountered difficulties at the start due to the system wanting to remain in economy mode all the time but finally fine tuned by Mitsubishi

Best advice is to find an experienced and successful installation team (electrician + plumber + refrigeration engineer + someone experienced in setting up these systems to your criteria). The Ecodan system is biased to always maintain hot water in preference to the heating system, apart from that we are extremely pleased with the system and its reliability

My RHI is £240/quarter and the system cost £12500 to install running costs are £220/month for my all electric house 

We also have a 4Kw solar panel system but would also recommend solar hot water panels

Obviously the costs would be considerably less if household temperatures were lowered, however not possible in my case

Hope some of this helps

 

CHRIS 

Wow, running costs are very high. Our last house was same size, late 60s and crap built 5 bed detached. Fitted new rads, plumbing and posh veissman combi boiler for 8k (done by tradesman) and cost to run was around 60 to 80 quid a month inc gas cooker. So around 120 ish for gas and elec. 

[joth]

59 minutes ago, Jeremy Harris said:

This comparison is only possible because I have an accurate (6 minute sampling period) record of our actual energy consumption.  Anyone who doesn't have accurate data to at least half hourly sampling just is not going to be able to compare tariffs at all easily.

 

Also bare in mind that even with a very accurate record of historic usage, while better than nothing, is going to be less and less perfect for gaining a genuine illustration of future savings potential unless you can also augment it on a half hourly basis with what % of your demand was unavoidable/unmovable, and what portion you could easily (and ideally, automatedly) have time shifted to another point in the day had a different tarif offered incentive for you to do so.

This is certainly a second order effect, but it's a bit of a schrodinger's cat problem. All forms of dynamic pricing since E7 are intended to alter behaviour (of people or systems), but without actually running it for a while it's extremely hard to predict how much demand shift will actually occur. The comparison sites don't have a chance at getting this right.

It leads me to think the big battery in every house will not come about because it's strictly economically justified, more because it gives a glimmer of hope of returning the masses to a predictable pricing model. It wouldn't be crazy if the price comparison sites strike deals to offer discounts on batteris, simple so they can get back to building in some kind of guarantee about overall cost/usage ratio.

 

[eandg]

Hijacking this a bit but I'm getting quotes in just now and the couple I've had so far for an 8kW system are around the 9 grand mark, for supply and install of the ASHP and hot water tank and MCS certification. Does that sound reasonable?

[Jeremy Harris]

8 hours ago, joth said:

 

Also bare in mind that even with a very accurate record of historic usage, while better than nothing, is going to be less and less perfect for gaining a genuine illustration of future savings potential unless you can also augment it on a half hourly basis with what % of your demand was unavoidable/unmovable, and what portion you could easily (and ideally, automatedly) have time shifted to another point in the day had a different tarif offered incentive for you to do so.

This is certainly a second order effect, but it's a bit of a schrodinger's cat problem. All forms of dynamic pricing since E7 are intended to alter behaviour (of people or systems), but without actually running it for a while it's extremely hard to predict how much demand shift will actually occur. The comparison sites don't have a chance at getting this right.

It leads me to think the big battery in every house will not come about because it's strictly economically justified, more because it gives a glimmer of hope of returning the masses to a predictable pricing model. It wouldn't be crazy if the price comparison sites strike deals to offer discounts on batteris, simple so they can get back to building in some kind of guarantee about overall cost/usage ratio.

 

 

The main problem I've hit is that there is only so much load shifting that's practical.  We're at that limit, in that as much as possible has been switched to overnight, and there's nothing more of any significance that can be time shifted.  I would guess that many consumers just won't wish to, won't know how to, or just can't be bothered with time shifting usage to fit a variable ToU tariff.  Experience seems to have shown that few consumers really make optimum use of simple long standing ToU tariffs, like E7.

[SteamyTea]

25 minutes ago, Jeremy Harris said:

The main problem I've hit is that there is only so much load shifting that's practical

Load shifting is easy if your loads are higher, at the moment, because I have the heating on, I am using 90% during the E7 window.  Not so great in the summer.

But I still manage, on average, to use 83% at night.

Edited February 8, 2020 by SteamyTea

[Jeremy Harris]

13 minutes ago, SteamyTea said:

Load shifting is easy if your loads are higher, at the moment, because I have the heating on, I am using 90% during the E7 window.  Not so great in the summer.

But I still manage, on average, to use 83% at night.

 

 

I agree, but there is still only so much anyone can practically do.  All our heating and hot water is already load shifted, as is charging my car and charging the battery pack that runs the network stuff in the house.  On dull days the washing machine is also timed to run overnight.

 

The rest is either on 24/7, like the sewage treatment plant, water UV disinfection unit and MVHR, or cannot practically be load shifted, like cooking, watching TV or running the water pump when we need water.

 

Because our house is all-electric, we can probably load shift a fair bit more than most, but I still can't get a variable rate tariff like Agile to work well.

[SteamyTea]

 

1 hour ago, Jeremy Harris said:

there is still only so much anyone can practically do

If I had a couple of kWh of storage, and a 6 kW inverter, I could probably get to 98 or 99% night usage, but with usage at under 5 MWh/year, it does not seem worth it to me.

All I would be doing is swapping my horrendous EDF day rate of 22p/kWh, or on average, 33p/day, to my not so good anymore EDF night rate of 9p/kWh, so a saving of 18p/day.

To get back £1000 would take 15 years.

And I doubt that I could get the kit for £1000, more like £3000.

[Benrh]

Well decided to bite the bullet and go for the 12kw LG, 210 slimline tank plus 9 rads for £13k. Will take some before and after pics once installed and see how things go. Thanks for all the info and guidance ?

Edited February 12, 2020 by Benrh

[farm boy]

Interesting reading. I am doing a140m2 self build. Got to make final decision on heating in next couple of months. Original choice was oil boiler with underfloor heating on the ground floor and rads upstairs.Now considering oil boiler first with the plumbing to heat pump spec. Then ashp later as pot of money getting lower every day. Other trades have told me that all the heat pump quotes are being priced to the subsidy and i would be better  installing  myself and not claim any subsidy. Anyone done this?

[ProDave]

Yes I paid under £1K for an ebay bargain ASHP subsidy and no RHI, self installed.

 

It was not a smooth ride, the first one I received was faulty and I had to kick up a stink to get a replacement.

[K78]

35 minutes ago, ProDave said:

Yes I paid under £1K for an ebay bargain ASHP subsidy and no RHI, self installed.

 

It was not a smooth ride, the first one I received was faulty and I had to kick up a stink to get a replacement.

 

I think this is the way to go.
 

They seem simple enough to install from what I can see. Am I missing something?

 

I can’t get my head around the cost of RHI installations. 
 

This is the one part of my build I’m undecided on. Gas combi or ASHP. 

[farm boy]

How easy was it to install? 

I am not sure but i think that outside of the RHI scheme ASHP are unregulated so any one can fit one.

[Jeremy Harris]

Took me about half a day to install and commission a monobloc ASHP, and I'd never installed one before (and I'm not a plumber/heating engineer).  They are dead easy to install.  The hardest part is setting the things up well, as the manuals are often pretty damned impenetrable.

[ProDave]

It wasn't difficult to install. all I will say of the three or so ashp's I have seen they all have a totally different electrical / control scheme, so just a case of read and understand the manual, which as above is not always straightforward.

[joe90]

Yup, I installed mine easily but the programmer is sooo complicated (on mine) I use other controllers.

[simon45089]

I am in exactly the same boat as you farm boy and seem to have had the identical thought process. I just need to figure out the correct size pump I need and do some sums. I have a relative who installs aircon so may approach him if I decide to go DIY, which is now very likely, since I recently had a quote from an accredited company for a full supply and fit for well over 20K !

[farm boy]

As mine is a new build I may have check with building control on a DIY ASHP fitting. But I like the idea of the lower up front cost as with most self builds money can always be spent in another part of the build.