Find a Solar Panel Installer you can trust near you.

How Many Solar Panels And Batteries To Power A House?

Do you wish to know the number of solar panels and batteries sufficient for a house? Well, this is a frequently asked question in the solar world which would be very difficult to provide an accurate answer. This is basically down to the fact that all homes are unique with different sizes as well as amount of daily energy requirements. As a result, the number of solar panels and batteries needed would be unique to the house in question. However, we’ll consider the varying influencing factors that will go a long way to help calculate the number of panels and batteries needed to power a house.

First and foremost, let’s take a look at the solar panels. You’d have to start here by putting into consideration all household appliances that makes use of power in the house to get a good idea of how many that’ll be needed.

• How Many Watts Is Being Used In The House On A Daily Basis?

To determine this, simply go through your utility bill for kilowatt-hours (kWh). This varies amongst homes and being able to identify your daily average energy usage will assist you in getting your solar needs.

• What Is The Number Of The Peak Sunlight Hours At The House’s Location?

Having in mind that the solar panels only work when under direct sunlight, the first step to determine the peak sunlight hours. Once determined, you can then multiply the figure in hours by the house’s hourly energy usage and divide by the solar panel’s wattage.

Overall for a 1500 square foot house, the number of solar panels that’ll be required should fall around 15 to 18.

Meanwhile for batteries, there are also some factors to be considered to determine the number of batteries that is required to power a house. These factors include the house’s power or electricity usage, the period of time in which the battery will be used as well as the battery’ specifications.

How Do Solar Panels And Batteries Work Together?

With solar panel system rapidly becoming an ubiquitous phenomenon within the modern society, several homeowners in the UK are just coming to terms with the numerous benefits offered by the system. The solar power’s popularity has even led to the rise of another renewable technology - solar batteries able to store excess solar power that can be used later. Now several companies such as Tesla are now building solar batteries that can be fitted alongside solar panels for your building. So how exactly do solar panels and batteries work together? Let’s have a look!

Solar panels make use of the sun light to generate electricity and as a result, they can’t function when sunlight is absent - giving a big issue of how to power your house when it’s dark. In the event whereby this occurs, you’re afforded two options which is either to contact energy providers to buy electricity or purchase a battery storage system.

So what’s the function of the battery storage system? Basically when your solar panel provides electricity which is not needed right away, a solar battery will work to convert the DC electricity into AC energy which is going to be stored for later use (when you actually need it). in other words, your solar panels charge the batteries when you do not require the energy they’re generating right away.

As a result, when it’s dark and the solar panels are no longer functioning, your system will tap into the energy that’s already been stored by your battery for later use. This way, you can be totally independent of the National Grid, which implies more savings on your electricity bills.

How Many Solar Panels And Batteries Do I Need?

Are you presently considering adding a solar system to your home? With several homeowners in the UK using solar now, many more are realizing the numerous benefits they stand to derive by getting one. Therefore, if you’re thinking about adding the system to your home but do not know where to start, you’ve come to the right place.

Here, we’ll help you calculate the number of solar panels and batteries you’ll need to power your home. Starting from the panels, you can begin by taken into account everything that makes use of power in your home to get a good idea of how many you’ll need.

• Firstly, you’ll have to determine the number of watts you use. Simply go through your utility bill for kilowatt-hours (kWh). This varies amongst homes and being able to identify your daily average energy usage will assist you in getting your solar needs.

• Secondly, you have to determine the peak sunlight hours - having in mind that the solar panels only work when under direct sunlight. Once determined, you can then multiply the figure in hours by your home’s hourly energy usage and divide by your selected solar panel’s wattage.

Generally for a 1500 square foot house, you might need around 15 to 18 solar panels to cover the house’s electricity.

Meanwhile for batteries, there are also some factors to be considered to determine the number of batteries you’ll need for your house. These factors include your home’s power or electricity usage, the period of time in which the battery will be used as well as the battery’ specifications. Once done, you’ll be able to calculate the number of batteries required by your home.

There are two different types: flat plate, where lots of thin tubes carry water through a flat absorber panel, and evacuated tube, where vacuum glass tubes capture the sun’s energy directly. There is little difference in performance between the two but evacuated tube panels do more obviously extrude from the roof.

1. After the installer’s measured up, given you an estimated output and recommended some systems for you, they’ll arrange date to come to your home to install the solar thermal panels. They’ll also let you know if any scaffolding will be required.
2. Next, they will start to fit the panels, or collectors, to your roof. Stainless steel brackets will be provided with the system and they will remove your roof tiles or slates to attach the brackets to the rafters. They’ll then replace the tiles and add waterproof flashing to ensure you don’t get any roof leaks, and add the frame.
3. If you’ve chosen evacuated tube solar thermal panels, the installer will bolt the heat transfer unit to the top of the frame but not install the tubes until nearer the end. This is because the tubes start to transfer heat to the exchanger immediately, and when everything is unconnected this could damage the unit.
4. If you don’t need a new boiler with your installation, a new dual coil water cylinder, pump and system control system will be fitted. It’s best in a loft or upper floor of your home.
5. A new thermal store or hot water tank that will store the heat provided by the solar system is much larger than a standard tank but it may fit in the spot of your old one. The installer will ensure that it’s connected to the mains cold water, your other heating source (such as a gas boiler or biomass boiler), immersion heater, temperature sensors and the solar collectors themselves.
6. Next they will install the pumping station, usually near the water tank. The expansion tank will be installed on the solar thermal loop, which is usually nearby. Its job is to prevent pressure changes that could damage the system.
7. You’ll get a heat generation meter which must be MCS-certified if you want to take advantage of the RHI, and any control equipment that comes with the system will be installed.
8. The installers will then bring the system to pressure by pumping the heat transfer liquid into the system up to a pressure of around 2 bar.
9. Finally, your MCS-registered installer will register your solar thermal system so you can apply for RHI payments of up to £525 per year.
So that’s the process of installing solar thermal panels. Remember – it's always best to use a professional to install any kind of renewable technology.

It’s vital to purchase a solar panel system that suits your property. If you’re investing in a solar panel system, it makes the most financial sense to get the biggest one possible. However, whether you can do this or not depends on budget and space.

Here’s an idea of how much roof or ground space you’ll need to install a few different sizes of commercial solar panel system.

Solar panel system size, No. of solar panels, Approximate area required

11kW, 44, 64m²

20kW, 80, 116m²

30kW, 120, 173m²

40kW, 160, 231m²

50kW, 200, 288m²