New build - Scotland - solar panels

player1_2

Hi all, 
I am in the process of buying a TW new build in Scotland which has solar panels as standard. Can anyone advise whether TW or other house builders in Scotland also install batteries , and are batteries necessary to realise savings ? 

ProDave

I doubt batteries will be supplied.  Excuse me but I am a bit cynical of a lot of the large house builders.  The only reason the solar panels are there, is to get just enough SAP points to scrape through building control requirements.  If they built the houses a bit better quality they would pass without solar panels.

There are usually not many panels, and the best way to make use of them is set some of your domestic appliances, like the washing machine etc to do their cycle around mid day, on a timer if you will not be in.

boots_babe

Batteries are not necessary but will likely optimise your savings.  Without batteries,  you only benefit when the sun is out at the same time as you're using power.

In reality these 2 things don't always coincide.  So being able to store the generated power in a battery means you can use it when you need it, not just when the sun is out.

Niv

Depends what you use your electricity for and how you are prepared to use your batteries to determine if a battery is economically viable. If you have ASHP then it more likely is worth getting - however if a very small array I would not bother.

A lot of builders install very small arrays (around 2KW), It will give you savings but it is a small array. Assuming you go with the new build, it is worth finding out how big the array is AND how big the inverter is so you can determine if it is worth adding more panels etc.

Niv

boots_babe said:

Batteries are not necessary but will likely optimise your savings.  Without batteries,  you only benefit when the sun is out at the same time as you're using power.

In reality these 2 things don't always coincide.  So being able to store the generated power in a battery means you can use it when you need it, not just when the sun is out.

My bolding - not true as there are export tariffs that pay around 15p per unit, so it is possible to benefit when the sun is out and you are not using all the electricity you generate. 

Also, regarding batteries, you would want to do a cost benefit analysis, No point 'optimising your savings' on electricity generation to save £50 a year if your battery costs £1k for example.

peter3hg

ProDave said:

I doubt batteries will be supplied.  Excuse me but I am a bit cynical of a lot of the large house builders.  The only reason the solar panels are there, is to get just enough SAP points to scrape through building control requirements.  If they built the houses a bit better quality they would pass without solar panels.

There are usually not many panels, and the best way to make use of them is set some of your domestic appliances, like the washing machine etc to do their cycle around mid day, on a timer if you will not be in.

I am in a relatively new build that was built with solar panels and the EPC/SAP was scored as though the panels weren't there so it passed the mark fine without them. In fact the main recommendation on the EPC is to install an identical system to the one already on the roof.
It doesn't have batteries and they have sacrificed some potential capacity by using integrated panels which look better but are generally lower capacity than on-roof panels.
To make the most of the system I installed a solar diverter to put excess energy in to the hot water tank, but with current export and gas prices I have this turned off at the moment.