The Robertsons have been farming 700-acre Cookston Farm in Eassie for over 70 years. Now in the hands of the 3rd and 4th generation. David Robertson, along with his brother, father and mother, run the farm together.
Potatoes, grown over 175 acres are Cookston Farm’s main crop — at any one time, approximately 3,500 tonnes of potatoes are stored in refrigerated cold stores, which require efficient energy to maintain a constant temperature of approximately 2.5OC.
We were a bit luckier than some our neighbours as our electricity contract was fixed at 26 pence per unit. But because further energy price increases are inevitable, it made perfect financial sense for us to investigate how to generate our own power from solar panels.
As a farmer, it’s important for me and for my customers that we have sustainable farming practices in place: renewable solar energy is an integral part of achieving that.
The installation was completed in March 2023 and now realise, we should have installed them a long time ago.
We contacted two companies to scope out our requirements and to provide quotes. We went with Forster primarily because:
We have a 68kWp roof-mounted system comprising 168 panels over four arrays.
Forster’s design engineers were very professional, and took time to understand our energy requirements and what we needed to achieve from our investment in solar. Instead of trying to sell us an off-the-shelf system, they tailored one to our particular requirements.
The system is configured so that it can easily be scaled up in the future to include a battery. However, Forster advised me to allow the system to bed in for a full year before considering any additional investment. This will allow me to make an informed decision on whether battery storage will meet my requirements.
Actual installation on the roof of the cold stores was very straightforward. It probably took two or three days over the course of two weeks for the job to be completed. The Forster team did everything from carrying out the initial site survey to design and installation. Importantly, they are very tidy workers — never any mess or clutter lying around during or after installation, which is pretty important on a farm like ours.
“The monitoring app that Forster provided is brilliant as it lets us see in real time the energy we are generating, shows us our consumption and the amount that is being exported back to the grid.”
With the panels we are able to use about 71% of our total generation. Currently we export about 29% of what we generate back to the grid.
To save more money, we time getting the loads ready for pick-up while the sun is shining. That way, we can use electricity generated from our solar panels to return the store temperature to 2.5OC when the doors are closed after drop-off.
My solar PV system was installed in March 2023 and already I am seeing a 40% reduction in my energy and my projected return on investment is 20%.
Because we were lucky enough to be on a low tariff, the payback period for our investment is around six years, which is a little longer than some of our neighbours, who, because they are on much higher tariffs, (some as much as 82p/kw) have shorter payback periods of about two years.
After six years, I can count the electricity generated from my solar panels as free.