Air Source Heat Pump: Electricity bills have tripled since having solar installed - any advice?

Can you tell us more about the heat pump, include some photos and say what temperature you have the house set to. The more you include the better.

Further thoughts: are your bills based on estimates, and is the solar correctly recorded as generating power ?

Hi, thanks for the reply. The bills aren’t estimates as I sent in an up to date reading. I am so ignorant about how this system works but we have 2 rads in the lounge set at 21 degrees on for 8 hours. Bathroom rad on for 2 hours at 21 and upstairs one rad on for two hours. Hot water is set at 60 and we use the shower once or twice a day. Have asked OVO for a visit from the Energy Efficiency Person but there isn’t one in my area.

If you can post photos of the outdoor unit, the hot water cylinder and the controller that would help. Are you using a Hive system to get those timings on the radiators ? There are a few things you can change on the setup which will help but I need to know what your system is. There are many makes of ASHP and the controls are all different!!

Juliamc has provided some great advice here, I hope that helps @serennu 

@serennu Have you had an opportunity to alter your heat pump settings ? Has that made a difference ?

Thank you for all the information you have sent me, I appreciate the time you have taken. What you have told me makes a lot of sense but I am not confident enough to alter any settings. I really need someone to show me hands on how to do it. I contacted Warm Wales and they have put me in touch with a local organization who will come to my home in the next two weeks. They will sit down with me and help me to find the best, most efficient and cheapest way to run this system

Hi @serennu that sounds like a very good idea. Do let us know how you get on. 

This stuff is complicated, @serennu, you will not be alone in being unsure of how to make adjustments to the heat pump and what adjustments would be optimal. OVO offer ‘Energy Experts’ visits, although I’d be curious how specific this advice can get around heat pump optimisations. 

Let us know how that visit goes. Was it free?

Thanks Tim, it really is complicated for an oldie like me. I asked OVO about the Energy Expert visits but my area is not covered at the moment, very disappointed about that as my county Powys are really pushing this Eco4 scheme and I am sure there are others like me in need of help in  understanding the ins and outs of my system. I am waiting now for the organisation to get back to me but was told it would be about 2 weeks because of the bank holiday. They are SevernWye,  a charitable organization and their services are free and they were recommended to me by Warm Wales. Thanks to you and juliamc  for taking the time to help me.

You’re very welcome @serennu My system went in 3 years ago. I knew nothing about heat pumps then and my installer told me not to touch anything !

I’ve been monitoring it and learning as I go.

What make is your heat pump ? Mine is a Daikin. I don’t have battery or solar.

​Thank you for sharing, @serennu. It helps learn what other resources are available if anyone else is in a similar position. 

We will wait to hear how your visit goes!

My heat pump is a Valiant. I too was told by installers to touch nothing, system would run itself. Do you not find it very expensive to run without solar or battery? I didn’t expect to make much of a saving through the winter months but I didn’t expect it to cost me the equivalent of my annual electricity bill either. I, like you are determined to learn as I go and am taking readings everyday. Hopefully will be savvy enough to avoid this happening next winter.

I don’t know the Vaillant controls unfortunately, however I’m sure the principles are the same for all heat pumps. Does your controller look like this ? 

I’ve added up the electricity bills for December January and February and they come to £731 (we only have a gas hob so that’s minimal). With solar and battery that would have been less of course. We have a 3 bed 1960s bungalow and I like it warm so it’s set to 22 degC. The main bedroom is 18 deg.

I should point out that only about half of the electricity usage in the bills total above was due to the heat pump ! Approx 1500 kWh for the three winter months.

@BPLightlog youve mentioned before about CT clamps being wrongly positioned. Is it possible that it could be pointing the wrong way and adding the generated power to the electricity bill ? 

It is possible but I would expect to have noticed that separately unless both were connected at the same time. 
It might be possible to check by comparing a sunny day to a cloudy one (should use less power from the grid on a sunny day) or even look at the monitor for the inverter. 

Can you see by looking at the clamp itself ? Would it make the usage fingers triple ?

You can but it’s not straight forward unfortunately. It depends on the system, set up etc but generally you would find the CT (probably near the meter) and look for the arrow that’s moulded into the side. It should be on the cable after the meter, pointing back towards the meter .. I’ll try to find a photo. 
If the previous usage noted was before the installation, then a CT positioned incorrectly could add double the solar feed level. (So possibly near to tripling). 
Edit: arrow not always easily visible 

If @serennu you are able to see a clamp like this and put a photo of it here that would be very helpful !! 
The more photos the better 

I can’t see a clamp, would it be near my meter or near the heating controls which are situated in my airing cupboard

It’s more likely to be near your meter if there is one there. 

There doesn’t seem to be anything like that in my meter box