Are you spending too much on energy?
The least energy-efficient potato stores use up to twice as much energy than the best ones, says Tim Pratt of Farm Energy Consultants (FEC).
With volatile energy prices, storage cost monitoring is playing an increasingly important role in maintaining profit margins, according to Tim Pratt, technical director of FEC who has recently concluded one storage project funded by Potato Council and has now commenced another.
“The results illustrate the advantages of simple storage energy monitoring to capture electricity consumption data that can then be compared month-on-month or year-on-year,” says Tim.
“There is significant potential to reduce storage costs, although the research brought to light some unexpected results where stores did not perform according to expectations,” explains Tim. “We are undertaking further investigation to examine underlying factors contributing to store efficiency.”
He recommends levy payers benchmark the performance of their own stores, using the Potato Council’s ‘energy hub’ section on the website www.potato.org.uk/energy to access reports showing data such as the monthly kWh/tonne and average kWh/day/100 tonnes in the current month or season to date.
“Our results have demonstrated that well maintained, well managed older stores can be as efficient as those built in the last five years,” he continues. “Furthermore, investing £15,000 to refurbish insulation can be repaid in as little as five years.”
Tim assures levy payers that energy monitoring need not be expensive. Simple analysis such as kWh/tonne/day can quickly highlight stores or periods when efficiencies fall.
Furthermore, efficient storage facilities can open the door to financial gain from long term storage. High quality, well-stored potatoes can be more lucrative as stocks can be removed from storage and sold when spot market returns are good.
The three-year energy monitoring project funded by Potato Council was conducted on 36 potato stores representing a typical cross section of GB stores.
“Some things, such as badly fitting doors and louvers, are obvious as soon as we enter a store” explains Tim. “However, others such as the efficiency of fans and refrigeration systems are not always so easy to quantify”. The next project will address this by looking in detail at the underlying characteristics of the good and bad stores. “The most interesting are those which looked good but performed badly”.
The focus points include:
• The whole of building insulation value, not just the thickness of the insulation
• Building air leakage
• Refrigeration system efficiency (COP)
• Fan efficiency
Air leakage in particular has great synergy with CIPC stewardship so there will be plenty of non energy related benefits coming from this project as well. Although this is a 2-year project, results will be relayed to growers as soon as they are found so expect to see regular updates very soon.