Zest Energy - System Set up Dilema

L1BYD

I am currently trying to help my Mum and Dad who had work done by Zest Energy (company based in Edinburgh) a few years ago. My Mum and Dad already had solar panels installed but a representative from Zest went to their home offering new systems etc. They ended up getting their existing panels enhanced, had a hot water tank system put in that heats their water from a panel outside and also 2 battery packs.  My Dad has just recently asked me to have a look at his bills as he says hes paying a lot and he absolutely is!!!  Their usage seems extortionate and I'm trying to navigate my way through all this.  My main queries are:

1. How do systems with solar panels work (we don't have solar panels) do you still pay an energy company for your full usage, as any other household would normally, then get reimbursed quarterly for your energy generated?  
2. The hot water system is set up and a temperature set for the water and if there is not enough power from the outside panel then there is an immersion that kicks in to get your water to temperature. But when we were looking at things it seemed the temperature had been set very high (over 60 degrees) and I wonder if the immersion has been on most of the time hence the high usage.  We have lowered the temperature and will see what difference it makes

I have contacted Zest on behalf of my parents and am trying to get my head round the whole system and try to understand how the bills / reimbursements work but its so confusing!  They are currently with OVO and have been for years (Scottish Power before I believe) and when I spoke to them about the extortionate bills they just said the usage was very high.  When I have spoken to Zest they tell me that according to their system they can see the system is working fine and we should speak to OVO.  I asked why the system has never been serviced or checked over the years, since installation there has been no contact with my parents whatsoever to check all working ok.  I have asked Zest to send someone out to check over the system but am told that they see its all working so its fine.  I have send another email to Zest explaining it seems crazy considering how much all this cost to install that there is then no follow up, no customer service afterwards.  The paperwork says there is a 10 year guarantee and I think my Dad has possibly paid MORE for an even bigger guarantee.  The last response I had was to say that the company owner is on holiday and there may be a delay in getting a response.  Can anyone help explain how these type of systems work so that I can try look at the bills to see if we can get cheaper deals elsewhere.  The Feed-In Tarriff they are on is also with OVO but obviously its "a different department" when you phone and its a nightmare getting anyone to explain things to me so that I can try help my parents.  Any advice very welcome!

Reed_Richards

Somewhere you should have minute-by-minute readings of how much solar power is being generated and how much is being exported or imported.  The first thing to do would be to find out how to access those readings and see if they seem sensible.

In my case I can see those readings via an app on my phone.  It's cloudy and my panels are generating 1.25 kW (out of a possible maximum of 4.8 kW).  My house is using 0.45 kW and the rest, 0.8 kW is charging my battery, which is 51% full.  No electricity is being imported or exported from my house.  And the exact readings change about every 3 seconds.  

tim_p

Do you have any numbers here? Panels power (kWp), battery capacity, (A)ctual electricity usage figures. Age of system and are they getting paid a FIT (feed in tariff for generation of system) Do they own said panels?
Basically more info needed. 

Qyburn

Is it a Solaredge system? That's what Zest were quoting us (although never actually sent a quote in the end). If so then you should be able to get access to their monitoring. Zest made a big thing of the monitoring and how the app let's you see exactly what's going on. For example live showing how much is being generated, and how much is being used by the house, how much exported ..

Qyburn

Regarding how solar panels affect bills, there's two aspects. Just the fact of generating power will reduce the bill, as the house will use available generation and only draw from the grid when there's not enough solar.

The second aspect is getting paid for "exporting" excess, when solar exceeds house use like in my screenshot. To get paid you need to positively sign up for an export tariff.

Hope this makes sense. I suggest going back to Zest to get access to monitoring and confirm exactly what's installed. If it is Solaredge there are a pile of settings around the battery which should be available to the end user.