Locally grown and climate-friendly apples.
Fruit grower Haak harbours the vision of one day operating his farm to 100% with his own energy. This is what led him to invest in a photovoltaic system and a CellCube energy storage system.
The use of fossil energy and the emission of greenhouse gases from cultivation to storage, transport and marketing and on through to the end consumer define the environmental relevance of products.
You hear it said time and again that an apple from Lake Constance or from the “Altes Land” region in the north of Germany leaves a greater track of CO2 in its wake from tree to consumption than one that comes from New Zealand.
This is however, not true for fruit grower Haak with his farm in the wonderful Altes Land region near Hamburg. He has decided to generate as much of the energy he needs for cultivation through to the sale of his apples from renewable sources using a photovoltaic system and also to buffer this electricity in an energy storage system so it can be used on overcast days or at night.
“We had really only intended to set up a PV system, but then we heard about energy storage and after looking into the options we decided to purchase a CellCube FB 10-100 which GILDEMEISTER energy solutions had offered us at a good price,” explains Claus Haak, who together with his wife and
son Henrik run the farm in the fifth generation. So in the traditional agricultural region of Altes Land the Haak family has taken on a pioneering role in resource-saving energy generation and harbour the vision – one that will hopefully soon come true – of running the farm to 100% on the energy they produce themselves completely independently of the public electricity grid.
HIGH ELECTRICITY REQUIREMENTS
There are several reasons for wanting this, explains Haak. Firstly, unlike most fruit growers, Haak stores all the fruit he harvests from 27 hectares himself and that pushes up electricity consumption, his farm in fact consumes around 125,000 to 150,000 kWh A kilowatt hour (kWh) is the amount of energy equivalent to powering one kilowatt (1 kW) for one hour (1 kW x 1 hour). Accordingly, there are megawatt hours (1 MWh = 1000 kWh) gigawatt hours (1 GWh = 1000 MWh = 1 million kWh) and terawatt hours (1 TWh = 109 kWh = 1 billion kWh). 1 kilowatt hour of electricity is equivalent to 17 hours of light from a 60 watt bulb. a year and that is a lot of electricity. Such storage entails keeping 1,250 tons of “hibernating” apples in cold storage. Because apples are living things that absorb oxygen, which of course, ripens them. That is fine for the early varieties that are delivered directly for sale to customers between August and October after harvesting. But this is the exception to the rule, because not all varieties of apples can be sold immediately.
Once the early varieties are harvested, the farmers in Altes Land go out again and pick different kinds, such as the German favourites Elstar and Jonagold. Some of these are stored for up to nine months so lovers of fruit in Germany can enjoy home-grown apples all year round.
Fig.: The automatic sorting system needs electricity all year round – electricity that Haak now generates locally with a PV system on his roof..
The Haak family has temperature-controlled storage facilities on their farm where the apples are kept in so-called “Ultra- Low-Oxygen storage”. This is an age-old method of storage which allows fruit to be kept for a long period without the need of chemicals. The farmer uses a special system to increase the natural nitrogen content of the air thus forcing the oxygen out of the room. The lower the oxygen level, the stronger and faster the nitrogen slows down the metabolism of the fruit. The fruit grower goes on to explain: “This results in the apple breathing more slowly which in turn delays its ripening process. Apples can be stored relatively long in this way.”
All very well, but these systems need a lot of electricity. And not only them. The automatic sorting system that Haak also uses to sort other farmers’ apples is another electricity guzzler. And electricity is expensive. Although the electrical power is controlled via a peak load limiter, in order to keep peak load values low.
“We do try to manage with that,” says Haak, “But we need a lot more electricity in autumn during harvest time.” This is when the apples are put into storage and have to be cooled very quickly – and a million kilograms of apples take quite lot of cooling! The limiter then ensures that the cooling units are switched off before the set peak load value is exceeded. Cycles of five to six minutes are not good for the cooling system in the long term.
GENERATING AND STORING YOUR OWN ELECTRICITY
“I would love to cut off the connection to the grid and be completely autonomous where electricity is concerned, and perhaps we will even manage to do it,” says Haak. “We want to produce our electricity ourselves. That is why we have installed a 100 kW Kilowatt (kW) is a unit of electrical power (energy consumption over time), 1 Kilowatt is equal to 1,000 watts. photovoltaic system on the roof, a big advantage for us in summer and autumn because we can get a lot more electricity than we do now.”
A CellCube energy storage system has also been installed on the farm so that the self-generated electricity is also available at night and any surplus electricity produced on particularly sunny days can be collected and buffered. “I want to offer a good product, apples that have a small CO2 footprint. People say that apples stored over a long period of time produce a lot of CO2 so it is better to buy apples from abroad! That cannot be true. And it isn’t; even German apples that have been kept in cold storage for eight months use up less energy than it takes to transport apples from abroad conveying them half way around the world on ships or lorries. With our solar and storage solution we are trying to convince people to buy domestically grown fruit and to do it all year round.”
“This is a modern agricultural region where we do not shut ourselves off from new ideas,” says Haak. “The investment will pay off in about ten years. What we also need is an energy mix of both sun and wind, because in our region in particular it is always windy. ”The innovative fruit grower has already put out feelers in the local council in this direction and would like nothing better than to order four of the WindCarriers also offered by GILDEMEISTER energy solutions. “I think the wind turbines are representative and futuristic and after all we have a lot wind here. I would love to utilise it.”
This would bring the fruit grower Haak a step nearer to his vision of energy independence – and Germany could enjoy locally grown apples stored in a climate friendly way with a good conscience.