The skyrocketing energy prices in 2022 are a huge challenge for potato growers. After all, ensuring good storage conditions in storage areas with the aid of fans and cooling installations costs a lot of electricity. As a result, the margins of growers are under considerable pressure. What can you do to save energy, Restrain asks in a recent blog post.
Fans consume a lot of electricity. In addition, if they run for a long time, they can deteriorate the storage conditions in the potato storage, according to Adrian Briddon, Technical Manager at Restrain. “Internal ventilation mixes the air in the storage into a homogeneous mass. If the CO2 level then becomes too high, growers have to ventilate their warehouse for a long time to drive off enough carbon dioxide. However, this also leads to fluctuations in temperature and humidity.
Those changing conditions can lead to weight loss and poorer baking colors in potatoes. To then straighten the temperature again, the cooling installation must be switched on. This again consumes a lot of electricity. Luckily, there is a smarter way.
Lower the CO2 level and keep other conditions the same
After Restrain discussed the energy challenges with growers, they developed a solution: an energy-efficient CO2 extractor that only switches itself on when the carbon dioxide level in your store gets too high.
Briddon explains how the solution works: “The extractor extracts the excess CO2 without affecting the other conditions in the storage facility. The grower places the extractor low to the floor, where the CO2 level is highest. The exhaust exits through a hole in the wall. This can often simply be done via the existing nebulization port where CIPC used to be injected.”
According to Briddon, the biggest difference between the extractor and ordinary fans is that the hatches of the shed can remain closed. “In February 2021, growers had to deal with outside temperatures of -18 to +18 degrees Celsius. At such times, it was impossible for them to ventilate their sheds without drastically deteriorating storage conditions. This led to very high levels of carbon dioxide in sheds, which is bad for baking colours. The CO2 extractor prevents this.”
Vent Timers vs CO2 Extractor
Some growers work with timers on their fans to save energy on purifying the air in the storage of CO2. According to Briddon, this is not ideal: “Every time growers air out their warehouse unnecessarily, this is at the expense of moist air in the storage. That can lead to additional weight loss. To minimize these losses, ventilation must be smart and energy efficient. That is why Restrain’s CO2 extractor only kicks in if the CO2 value gets too high.”
Saving energy pays off within a month
The payback period of a CO2 extractor is extremely short at current prices, says Briddon: “In a first case study with the Restrain CO2 extractor in Finland, growers reduced the use of the main fans by fifty hours in one month. In the UK, in a storage facility containing 1,000 tons of potatoes, two CO2 extractors replaced fifty percent of the energy consumption of an 86 kilowatt main fan for carbon dioxide control. The cooling of 111 kilowatts also needed to run an hour and a half less per day. With these energy savings and current energy prices, growers can earn back a CO2 extractor within two weeks to a month!”