Northumberland Council HQ Carpark


When I wrote this submission, Newry Mourne and Down Council’s total electricity bill was £913,894. But it now over £1 million.

Council was paying an average of 14p per Kwh in 2021 – so this translates 6,527MWh’s of power per annum to power the dozens of facilities from Saintfield to Crossmaglen. (The average unit charge per Kwh has increased since 2021)

Strangford's Inverbreena Hall - one of our smaller PV installations
Strangford’s Inverbreena Hall – one of our smaller PV installations

In the past our ex-energy officer did refits of many community centres using PV panels – see report here Accumulated Annual Savings March 2017 energy efficiency march 2017.

As you can see, before our energy efficiency program was abandoned by Council management in 2017, Council typically had a 7 year payback , (first page of 2) on PV installations on Council buildings by not using fossil fuels or mains power.

Since that time, PV costs have dropped by 2/3rds giving PV a payback time as low as 2 or 3 years – were Council to go back to doing energy efficiency projects again. No other investment can give Council such a handsome return.


Fortunately, we were given an excellent steer on what to do here in a presentation to our Councillors at the Killeavy Hotel in South Armagh by Andrew Oswald, Environment and Energy officer for West Suffolk.

West Suffolk has been investing in renewables for the benefit of ratepayers for years
West Suffolk has been investing in renewables for the benefit of ratepayers for years

Using West Suffolk Council’s figures from our Killeavy Castle conference, we can get 752MWhs of power per hectare from PV.

This means NM&D needs 8.7ha to cover our entire £913,814 energy bill.

This would mean a capital investment of £578.77 per MWh, or a total capital investment of £3.77 Million if the panels were laid on agricultural ground.

Using figures from Council’s Finance department, the NM&D borrowing cost pa for this would be £175,678 per annum.

The annual positive cash flow would be £913,814 – £175,678 = £738,136. This suggests a 5 year pay-back as we are not just supplying the grid at the normal export price of £60 per megawatt but cancelling our own energy costs from our own buildings at £140 per megawatt. (NB 2021 figures – we would get a lot more than a £700,ooo positive cash flow now)

BUT We don’t have 8.7ha of agricultural land beside n ost our most energy-hungry buildings. HOWEVER we do have car-parks.

(Also, to wipe out our energy bills entirely we would price in batteries for night time operation. But that could be a second phase.)


The Council’s Active and Healthy directorate has 133 carparks spread right across the district. (list attached). These car-parks are ‘dead assets’ making no money for Council but requiring maintenance. Some buildings have carparks managed by Council’s ERT directorate (covered in tomorrows COP28 post) and the South Eastern Health Trust.

Most energy-hungry Council buildings sit beside a Council car-park. These buildings were built at a time when Council Management still considered fossil fuels as “primary power” systems and when they considered renewables (if they were considered at all) it was just as “secondary power” systems. About 20 years ago renewable energy systems became cheaper than fossil fuel systems in new-builds. We should have been installing the cheaper options of PV and Heat pumps as the primary systems, with oil and mains electricity only as the secondary supporting systems. The Downpatrick and Newry Leisure Centres are particularly disastrous examples of this. But we are where we are.

Our old energy officer’s retrofit of renewables – mostly PV – plus energy/water efficiency program has made a huge £100,000pa dent in energy costs, but we need to get these costs down to a ‘zero-cost and zero-carbon’ level and eliminate unnecessary fossil fuel and mains electric energy costs.

All our successful PV retrofits to date have involved a capital cost of £1,250+ per Kw installed and gave us returns of 7/8 years.  But costs have dropped by 2/3rds making PV carports affordable.

The median 2023 cost to convert a mid-range carpark using car-ports to supply energy is around £1,250/kWp for V frame carports. A 250 bay carpark gives a 600kW installation, producing ~500MWh’s pa. This is a 10 year payback on an average 14p per kWh. BUT during daylight hours energy costs are normally higher, so the payback would be more like 7/8 years.

I have photos below of organisations below who in years gone invested wisely and are now reaping huge financial benefits


In thousands of examples across the UK, Councils, businesses, factories or retailers are using their car-parks to generate energy and wipe out the cost of running their buildings. Many are adding in batteries for EV charging points to make additional money.

A typical example is Nottingham Council who have many such installations. See one of their Leisure Centres here

Nottingham Councils Leisure Centres
Nottingham Councils Leisure Centre’s car park

Councillor Alan Clark, Nottingham’s portfolio holder for energy and sustainability, said:

 “The solar carport is an ingenious solution for maximising our assets, generating income and lowering the city’s carbon emissions. Car parks, although serving a practical purpose – and very necessary for our thousands of customers that visit our leisure centres – are not usually seen as cutting edge. It’s really exciting that we have been able to extend the usefulness of this space and invest in a green energy supply for Nottingham.”

Batteries can also be installed to run the Leisure Centre after dark or to charge EV’s.


Our total cost of Electricity for the year ended 31st March 2020 was £913,894. This included the new Down Leisure Centre at £126,749pa.

What Downpatrick Leisure Centre Car-park might look like
What Downpatrick Leisure Centre Car-park might look like

This huge Downpatrick £127k figure arose from Council Management blocking Councillors requests for the installation of a PV roof, plus ground source heat-pumps and other green options at the new leisure centre. Management produced an ‘independent’ report showing that oil-fired boiler supported by mains electricity has a better payback. I am not making this up. It really happened. I will be publishing documents on this case towards end of this COP28 series.

This means that the Downpatrick Leisure Centre as currently configured needs 905 MWh’s pa just for its current electrical power needs alone.

Firstly we would have to carry out the long-delayed energy efficiency project to install PV on the roof of the centre and get rid of the small uneconomic solar water system that was installed by management of this project as a sop to Councillors. This PV project would have a payback of ~4 years and can be done ahead of a more expensive carport project because Councillors approved it years ago. If we assume 100 panels at .35kw per panel = 35kw installed x annual conversion rate 850 giving about 30MWh’s per annum. The Sustainability committee in Council passed the above project, as well as a number of other projects but the lack of an energy officer has delayed them.

Thus we have well over 800MW’s of unfulfilled demand for a carport project on this site that can be met from PV car-ports.

Secondly, if we install the sort of V frame carports you see in the above picture at £1,250/kWp we could expect a 600kW installation, producing ~500MWh’s pa during peak daylight hours giving us a payback on investment of between 7 and 10 years. If we replaced night-time energy consumption with batteries it would be more like 10 years. On this site alone we cold reduce electricity bills by £70,000 pa

NOTE – these structures do not have to be installed only over car-parks. They can be along public walkways around Dunleath Park. They could even be installed at the 2 ERT 400-bay carparks across the road at Market Street and wired across. The possibilities change with each site.

As can be seen by these figures, prices have dropped so low for PV at this time, that embarking on a major project to largely eliminate our £913,894 energy bill is now very definitely feasible.


Northumberland Council HQ Carpark 

Northumberland Council HQ Carpark
Northumberland Council HQ Carpark


Aviva's Scottish HQ using PV for power and energy storage to wipe out power bills
Aviva’s Scottish HQ using PV for power and energy storage to wipe out power bills


Aviva facility in Peterborough has 1000 staff and a zero energy bill during daylight hours
Aviva facility in Peterborough has 1000 staff and a zero energy bill during daylight hours

Aviva Insurance is using building carparks for PV electric power and energy storage in Norwich (left) where 1000 employees are based and  has no power bill during daylight hours.

At its Scottish HQ i(right) t also uses energy storage to ensure renewable power is available 24 hours a day.



Bentley Motor Factory - £400,000pa electricity all consumed on site
Bentley Motor Factory – £400,000pa electricity all consumed on site

The Carpark at Bentleys Motor Works generates £400,000 pa of electricity which is entirely consumed on site.