ASHP pump compatibility with power Supply

[Adrian Jenkins]

Hi All

I’m new to the group and not actually an electrician. But please don’t hold that against me!

I’m after some advice please. I’ve come to a point in my building renovation where we are about to install a heat pump. Stiebel Elton WPL 25AS the forms for the pump had been filled in and sent to the DNO Western Power Distribution. But they have come back to say I can’t install due to the “harmonics” that this will cause on the feed in our street.

If I want to use it we need to reinforce the power supply to our house at a cost of £18,000!!! Payable by me.

Has anyone come across this before? Is there anyway to make the unit compatible such as a capacitor / resistor set up or Tesla battery before the unit?

Time is short as I’m at the project and don’t have time to enter into Westerns 6-8 week appeals process. At the moment I may have to go back to oil heating.

Any help or suggestion gratefully received. Thanks

 

[Pete999]

Did the DNO explain what they meant by reinforcing the supply? Did they offer any information to substantiate the 18K price quotation they expect you to pay? Sorry for the questioning just seems hard to get my head around what they are asking for. Good luck whatever the outcome.

 

[ferg]

In my experience ASHP's are only any good in incredibly well insulated buildings.

Otherwise they end up being very very expensive to run in the winter when you need them the most.

I live north of Hadrians wall though which may have a bearing on it.

 

[snowhead]

"Reinforcing the supply" will be increasing the supply cable size(s) either from your property back into the network or may just be increasing cable sizes in part of the network leading to your property.
You're very unlikely to win an appeal you, will have to employ experts in power network distribution to beat Western power's arguement.

£18000 in DNO work isn't much work, it may only be a few metres trenching and new cable.
You've probably already run out of time, it's usually a 3 month lead time for DNO works after the order is placed.

They should have supplied a breakdown of works costs .

 

[mhar]

Your electrician will need to speak with WPD.
The first response you would have had from them will include 3 telephone numbers. Your electrician will need to speak to the system / network planner whose number would have been included.
Being brutally honest, about the only explanation they would be able to give to you would be how much it costs which they have already done.
The price quoted could well suggest a new transformer off the hv network. If within 10 years this is then used for other supplies, you will be entitled to a partial refund.
A good electrician should talk a very similar language to the dno planners, be able to understand the issues with the proposed new demand and may be able to work with them for a solution if there is one available. Aren't ground source heat pumps significantly more efficient than air source ones, even if the upfront cost may be more?
A customer has recently been given a ball park figure of £18k for a supply to a single new house approaching the dno direct. All the dno were able to do is advise on costs for upgrading the existing network. After a site meeting with a network planner, informing him of two other plots just been granted planning permission, plus 15 holiday lodges and a campsite with ev charging, the ball park estimate for everything is 25k with the expectation of refunds from expected applications from a neighbour.
Sometimes you just need a professional.

 

[Andy-1960]

What exactly did you tell them when you applied for the supply?
From what I can see, this inverter controlled compressor within this unit is rated at about 230v 3.2kW.... I am very surprised they have thrown this out based on harmonics.
What size supply are you requesting?
Are you in a rural area?
Have you asked Stiebel-eltron for the harmonic information of the inverter fitted within the heat pump?
You're not planning on fitting solar panels as well are you? I know the DNO are getting very twitchy now about these.

 

[Adrian Jenkins]

Did the DNO explain what they meant by reinforcing the supply? Did they offer any information to substantiate the 18K price quotation they expect you to pay? Sorry for the questioning just seems hard to get my head around what they are asking for. Good luck whatever the outcome.

So they are quoting for:

Install 75metres of 185mm 3c wavecon onto new wavecon and potexisting service breach plus road closure required.

So in short dig up road and pavement in front of 5 houses and bury a new cable.

 

[Adrian Jenkins]

What exactly did you tell them when you applied for the supply?
From what I can see, this inverter controlled compressor within this unit is rated at about 230v 3.2kW.... I am very surprised they have thrown this out based on harmonics.
What size supply are you requesting?
Are you in a rural area?
Have you asked Stiebel-eltron for the harmonic information of the inverter fitted within the heat pump?
You're not planning on fitting solar panels as well are you? I know the DNO are getting very twitchy now about these.

Hi yes the installer is going back and questioning and I have sent a mail to Stiebel, which I’ll chase up next week. Just trying to get as much info as soon as I can as we are short of time. Yes in a small village just outside Warwick. What we told them was what they asked for on the tariff form. We have gutted and extended the house to latest insulation specs and applying external insulation. So pretty well insulated. Just want to get of burning kerosene if possible but utilities don’t make it easy!!

 

[Wilko]

Hi - just reading up a bit over lunch - apparently although the load is fairly small (no bigger than a cooker I reckon) the DNO are concerned about the level of harmonics generated by the invertor. It would be good to be able to read the form submitted and the comments returned - was it Form A on the link (?). I'm just being rude now and I've probably misunderstood, but asking you to pay for 185mm when you've added 6mm of load is a classic.
http://www.energynetworks.org/assets/files/electricity/futures/Heat Pumps/New Form A 11 Oct 2012.doc

 

[suffolkspark]

I dont install ashp but out of interest are you supposed to tell the dno when new ones are installed?