Skip to main content
Observer Ethical awards Winners 2011

YouGen Blog

Solar allowances to change in Northern Ireland

Posted by Andy Baird on 18 December 2013 at 12:01 pm

The size of solar installations allowed without applying for permission will reduce from 1 March next year. Under the G83 rules Northern Ireland Electricity (NIE) currently allows people to insall arrays of up to 6.5 kWp and 20 kWp on single- and three-phase supplies respectively. This generous allowance has enabled solar in Northern Ireland to establish itself, especially over the last 18-24 months.

From 1 March 2014 this will reduce to 3.68 kWp on single-phase, and 11kWp on three-phase supplies

NIE has also confirmed that the revised limit will be applied to the inverter rating. Therefore, a  4kWp array on a SE/SW array would be acceptable as long as the system uses an inverter rated no higher than 3.68kW.

While the change may seem unfair to both consumers and solar installers, there are sound reasons for reducing allowances. Larger domestic systems tend to export significant levels of solar generated electricity back to the grid. The NIE grid was designed primarily to push electricity from centralised generation plants to homes, and issues can occur when energy flows in the opposite direction. The new allowances manage risk issues associated with the export of solar and other sources of small-scale, renewable electricity.

Of course, there is now a window of opportunity to install up to 6.5 kWp of solar and installers in Northern Ireland are seeing a spike in demand as consumers race to beat the 1 March deadline. We’ve prepared a few points of guidance to help homeowners navigate through this period:

  • Deadlines are a salespersons dream! Solar is a long-term and significant investment so beware of pressure to sign up and avoid missing the boat... you still have time to get several quotes and work out who is the best fit for your project.
  • Ensure that your chosen installer can install on time with allowance made to submit G83 paperwork to NIE. Ideally, ask your chosen installer to help you complete this paperwork and post it using recorded delivery. NIE are unlikely to be able to confirm they have received your paperwork during this period, so ensure you can prove it was sent in time.
  • Consider if you really need to go for a solar array larger than 4 kWp. Ask potential installers to explain how much electricity your system is likely to export and how they’ve worked this out. If you’re likely to export more than 60% then the system is likely to be over-sized for your requirements. You could save some money by going for a smaller system and invest in other energy efficiency and energy saving measures.

The changes NIE are making are, at least in part a result of an increase in exported solar electricity from domestic arrays. Although there are real-world economies of scale when installing larger arrays on homes, because scaffold and electrical installation costs are less affected by the number of modules installed, smaller systems export less electricity. Solar economics are improved when you use the clean generation and save 16-17p per unit, rather than export and earn 5.96p so it makes sense to minimise export.

Those wishing to install >4kWp on a single-phase supply after 1 March next year will still be able to apply to NIE for a grid-connection study and the revised fees for this are due to be published shortly. Your installer will be able to review the published NIE 11kV Network Heat Map and advise where the network is already at saturation point. There are many areas with available capacity subject to NIE approval.

More information is available from the NIE website by clicking here.

We’ve long advised customers that, bigger is not necessarily better, and do not automatically recommend the largest system size a roof can accommodate. A well designed and installed, un-shaded array using high quality equipment and sized appropriately will provide valuable insurance against rising grid-supplied electricity pricing for decades. The new 4 kWp allowance still enables most typical households to cover their annual spend on electricity from solar savings and NIROC & export income. And many will still earn a small surplus.

These new limits bring N. Ireland in line with England, Scotland and Wales. With nearly half a million solar homes across the UK, approximately 5% of housing stock, continued uptake of clean and proven solar beyond 1 March 2014 looks inevitable.

Image provided by Andy Baird

More information on YouGen

YouGen's solar electricity information page

NIROC: the financial incentive for solar pv in Northern Ireland explained

How to check that you are getting the most out of your solar panels

About the author: Andy is founder and managing director of Planet Solar (NI) Ltd.

If you have a question about anything in the above blog, please ask it in the comments section below.

Like this blog? Keep up to date with our free monthly newsletter


0 comments - read them below or add one

No Comments.

Leave a comment

You must log in to make a comment. If you haven't already registered, please sign up as a company or an individual, then come back and have your say.