Explaining G98 and G99
EXPLAINING G98 AND G99
G98 and G99 specifically refers to different kinds of protection settings regulations that generator or storage assets must comply with to connect to the network.
The protection settings are an important fail-safe mechanism that protect both the network and the asset from potential faults.
WHAT’S THE DIFFERENCE BETWEEN G98 AND G99?

If you are connecting single or multiple phase generators at a single premises of up to16A(3.86kW) per phase you need to complete a G98 notification form.

If you are connecting single or multiple phase generators at multiple premises of up to 16A (3.86kW) per phase you need to complete a G98 application form prior to connecting.

If you are connecting large scale generation, above 16A (3.86kW) per phase or energy storage, then you will need to complete a G99 form.
We have a decision making tool that can help you determine whether you need to make a G98 or G99 application. You can access it here.
G98 IN FOCUS
You need to submit a G98 application if you are applying to connect a generation up to 16A (3.86kW). Depending on the nature of your project, you will be required to complete different forms.
If you are installing micro-generation at a single premises, you can make the installation but must notify us within 28 days of commissioning. The same criteria applies if you are connecting micro-generation at multiple premises that are more than 500 meters apart.
You can notify us online via this link or submit a G98 single premises application form.
If you are installing micro-generation at multiple premises in close geographic proximity, for example on the same street, you must apply to us before you can connect.
You can apply online via this link or submit a G98 Multiple Premises form.
G99 IN FOCUS
You need to submit a G99 application if you are applying to connect a generation asset that’s over 16A (3.86kW) or connecting energy storage. Depending on the nature of your project you will need to complete different forms.
If you are installing generation or battery storage to our network , you must apply using a G99 form. This can be completed via this link.
If you are installing battery storage, you may be eligible for the fast-track electricity storage applications process. The eligibility requirements can be found online via this link. If you do not meet all the eligibility requirements, you will need to apply using the G99 application process.
USEFUL LINKS
- For more information visit: northernpowergrid.com/get-connected/connecting-generation-storage
- G98 or G99? Our helpful guide can help you to decide northernpowergrid.com/generation-connection-guide