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

t0rt0ise

smart_taunton_bloke said:

markin said:

The first step i think is to get a smart meter, and move to octopus to get the best seg from the solar.

Hi Markin - do you know if I would I need to get the smart meter before I move to Octopus? Or would they install it? 

I moved to Octopus last October. They installed a smart meter in November. But it depends on your area how quickly they can do it.

[Deleted User]

smart_taunton_bloke said:

thanks everyone for your help with this.

I think initially it's going to be best to get a smart meter to see exactly what I am using/generating, then make a decision later in the year.

the heat pump options look great. 

A smart meter DOES NOT show you what solar is being generated. It will only show the amount of energy that your solar array is exporting to the Grid. The IHD display will show this as instant power (kW) and the meter will record total usage (kWh).

It follows that if your array is generating 2kW of solar energy and your house baseload is 250W: then the IHD will show that 1.75kW is being exported to the Grid.

For real-time information, you need a monitoring set up that is based on CT clamps:

pip895

I have managed to save 2/3 of my Electricity cost using batteries and a time of use tariff.  Provided your battery is sized correctly - The size of your daytime usage + ~20% you can assume that you should be able to swap around 95% of your peak rate usage for night rate. You will also increase your usage of solar substantially but this is more difficult to quantify. 

pcgtron

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 

Petriix

@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. 

Mstty

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.

markin

They are around average usage in the daytime with 3500, With the other 3500 on night tariff over 4 winter months averaging 875 a month, Size a battery for winter and you only use its full potential for 3-4 months a year, And the rest of the year they would only be using 20%-30% of it.

But without data its just guess work, The day/night split in the summer months should be far better with solar if they are at home to make use of it.

Not claiming the Seg has cost £200-300 a year!

smart_taunton_bloke

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

markin

Have you got some actual reading on bills over the last 2 years, or are they mostly estimated so useless?

smart_taunton_bloke

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

3525 day
440 night