I have existing solar panels and economy 7 heating - is it worth getting batteries?

pcgtron

Mstty said:

Petriix said:

@pcgtron at 1127kWh in a single month, you're an exceptionally high user. Batteries make perfect sense for you. Most people couldn't benefit anywhere near as much. 

Completely wrong analysis without knowing all the facts.

For example they are probably an electricity only household. Like us and we used 1007kwh in January as it is a high usage month for many people. That doesn't mean the yearly figure of usage is exceptionally high.


We're not an electicity only household, but an EV owning household (20,000 miles a year) so electricity split evenly between EV and house (About 5000kw for each thing). 
Jan is usually that high, there or there abouts. It does go down slightly in the summer, but we use 10,000 kw a year. Not charging the EV every day helps with that, although the cost at the moment is low. 

smart_taunton_bloke said:

pcgtron said:

My latest electric bill for January. 

£113.96

1073.1kw at the off peak rate of 7.5 pence

54.4kw at the peak rate of 40 pence

Some of the peak rate for Jan was because of load shifting for the saving sessions and using it on purpose. 

Batteries make this possible. We have 13kwh of storage and use very little peak rate electric if any on a day to day basis 

Thank you.  Thats a really low off-peak rate - mine is 15.7

We're on intelligent Octupus due to having an EV, hence the low rate. 

markin

smart_taunton_bloke said:

I switched to Utility Warehouse in March this year. From then until the End of December: 

3525 day
440 night

That's a not a great split for 10 month its around £300 off worse so far than a single rate and im not sure the next 2 months at 1000kwh a month on night rate will fix that.


I think you end up £10 better off at 4000 day, 3000 night. ?

AllanInness

Ive just fitted batteries to my existing solar (fitted 2010) .  My usage for a year is about 9000kWh split 85% night 15% day (tracked over 12 years)    Since fitting the battery (6kWh) in december, I now run all day on battery/solar and charge it up overnight.   the last week has seen my day electric charge of £3.02,  £3.12,  £2.96, £2.97, £3.13, £3.37 and £3.01.  (that includes the 46p standing charge.    Im with EDF  5.88p off peak and 51.92p day  

smart_taunton_bloke

@markin - looking at it again, I'm not sure those figures are accurate. It looks like I am using 120kw - 150kw of the night in the summer months, so 400 in total doesn't add up. Looking back through my bills they have made some adjustments somewhere. 

I used 700 nighttime in January this year.

smart_taunton_bloke

@AllanInness - thank you. I've just tried a quote with EDF and it's 15p nighttime rate. 

I do like the idea of having batteries, but think I need to get more accurate with my readings. 

AllanInness

smart_taunton_bloke said:

@AllanInness - thank you. I've just tried a quote with EDF and it's 15p nighttime rate. 

I do like the idea of having batteries, but think I need to get more accurate with my readings. 

Understanding your exact usage and profile of use is really important in sizing the battery...  look at past bills will give you an idea, but realistically you need to record the readings every month  and have multiple years of data to look at.   Panels always made sense to me, but it wasn't until the silly price hikes for electricity that a battery became worth it.  Generally I'm pleased with the battery size I have.. there isn't many days that I go over its capacity.. and I'm still learning the different usage profiles and what they actually mean for actual energy usage.