Solar energy comes from the sun so being able to capture that energy for free is only half the story.
A household will usually only directly use about 1/3 of their solar panels’ output so the remaining generation will go out the grid.
While the owner of the panels will get paid for the amount that is sent back to the grid this is usually at a low rate.
Being able to capture solar energy for free is only half the story when it comes to installing a solar PV system.
A household will usually only be able to directly use about 1/3 of their solar panels’ output so the remaining generation will go out the grid. And while the household will get paid for the amount that is sent back to the grid, this is usually at a low rate (about 5.5p/kWh compared to 15-17p/kWh at the time of writing).
This means that having a battery storage system can vastly improve the performance of a solar PV system by at least doubling the direct solar energy use within the household. This also means that solar energy will be available when the sun isn’t shining. Prices have been dropping steeply for home battery storage in recent years so these systems are now much more affordable.
A typical household will use roughly 10kWh per day so a typical battery setup will store about half of that amount 4-6kWh. The battery will go through one complete charge and discharge cycle each day.
Batteries can also be used to store energy from the grid at night when rates are cheap and discharge at peak times when rates are expensive. You will need to get a smart meter and go on a 24hr tariff to take this approach but it can add savings in addition to the solar PV system.
Solar panels produce electricity in direct current (DC) and batteries work in direct current as well. However, we use alternating current (AC) in our homes and AC current is supplied from utility grid.
A hybrid system utilizes a single inverter that manages both the storage of energy in the battery as well as the transformation from DC from the solar panels and battery to AC power for use in the home.
Electrical regulations require DC cabling to have a higher level of protection and shielding when installed in the home which involves metal ducting so may not be best suited for all installations.
AC couple battery systems involve a separate inverter for the solar panels and the battery system.
These are typically installed when adding a battery to an existing solar panel system or where running a lot of heavily shielded DC cable through a home or business is not practical.
AC coupled battery systems tend to be more cost effective despite the extra inverter so this makes them an economical choice.
We work with Edinburgh-based Sunamp products to supply heat batteries. A heat battery stores electricity from solar panels or the grid to generate heat for hot water.
Heat Batteries fit comfortably in tight spaces and are designed to provide cascades of hot water on demand. You can use them with solar PV and existing boilers. Plug one in to get hot water where you need it.
For larger homes, multiple Sunamp Heat Batteries can be easily linked, and work with heat pumps and off-peak electricity, to give you maximum comfort and significant savings.
Hot Water Solar Diversion
If your property has a hot water tank than you can easily install a hot water diversion system along with your solar panels.
This communicates with the solar panel inverter and when excess power is being sent to the power grid it diverts it to the immersion coil in your hot water tank. This turns the water tank into a very cost effective “heat battery” and keeps you in free hot water for much of the year.
An alternative for hot water heating if an immersion hot water tank is not available would be a heat battery.