If your usage is generally in the daytime, then a simple system of panels and inverter will be the cheapest option.  Being the cheapest, it is the fastest way of saving money on your electricity bill. You can use the PV calculation tools below to work out your needs



If your usage tends to be outside daylight hours, you will need battery storage to make the  most of your harvested power, without losing it all to the grid, which is good for everyone else, but won’t save you money!

It’s really easy to increase your battery storage with more modules, so base your battery size on the recommendation of your installer, an online calculator or use your budget to work out how much you have to spend on storage and get advice to ensure you don’t overspend.


How can I clarify how much solar I am allowed on my property?

This requires a face to face conversation with your installer and to inform or apply to your provider, to calculate how much solar PV you can fit and are allowed to install.  Your installer should assess your property and work with you to calculate your needs and make the application with you.


First Steps

You will need an MCS certified installer / Electrician to apply and fit your On Grid system.

Please note that an MCS certificate is not a mandatory or legal requirement for system installation.


Click below to read some helpful Government advice sheets on guidance for owners



Informing your DNO (See ‘What is a D.N.O?' below for context)

The size of your solar PV system will determine the type of DNO application you will have to apply for. It is worth noting that the size of your PV system is based on the AC inverter rating, rather than the peak DC rating of the panels.

The main two types of DNO applications are “connect and notify” or “apply to connect”.

G98 for under 16A per phase and G99 for over 16A per phase.

You must notify your DNO if installing:

  • Solar panels
  • Battery Storage
  • EV Charging
  • Heat Pumps

Click below to find out who is your DNO


The G98 DNO application for “connect and notify” is a free application, however administrative fees from your solar panel installers are usually charged in order to process the application. As for the G99 and G100 applications, they can cost from £300 upwards.

What is a D.N.O? Distribution Network Operator

Your distribution network operator (DNO) is the company that owns and operates the power lines and infrastructure that connect the national grid to your property.

Once you have gained approval we can work with your chosen MCS accredited installer, or with you, if you are suitably qualified to design the system architecture with us, to arrive at a system specification that meets your requirements, as well as those of a safe and certified installation.

If you haven't already done so, we strongly recommend you make your application for approval for a grid-connected system to your local DNO as soon as possible. This process can take between 15 to 45 days to complete, and is required for all grid-tied energy storage systems as well as solar PV systems (with or without storage). Your contracted installer will usually make the application for you.

NOTE: All PV Grid tied Inverters, as well as storage and hybrid inverters, are considered as generators. To be connected to the grid they need to have an approved G98/99 certification as listed on the ENA Website. Please check the G98/G99 compliance status of your product on the ENA type test register at the following link, this will ensure that this is suitable for your project.



What is MCS and why do I need it?

An MCS certificate is proof that your installation has been designed, installed & commissioned to the highest standard using only MCS certified products by an MCS certified installer. Please note that an MCS certificate is not a mandatory or legal requirement for system installation.

MCS certificates enable consumers to access financial incentive schemes and may be required by some mortgage companies before lending on a property. Being part of MCS ensures that customers are protected by a Trading Standards Institute (TSI) Approved Code of Practice.

To receive an MCS certificate Domestic pitched roof mounted installations must use PV Panels and roof mounting systems that are MCS approved.

Click here for the MCS website for further detailed information.

Click here to find local MCS Installers

Link to guide for FITs (Feed in Tariffs), the now closed Government scheme which paid you for electricity surplus

OFGEM Link for FIT