Old, decommissioned coal mines may serve as symbols of irreversible energy and environmental change, but scientists at the University of Nottingham (UK) have decided to find other uses for them. From their point of view, this is an ideal platform for creating vertical farms, transferring familiar greenhouses underground. A hefty amount of food can be grown here, providing savings on everything: water, land, energy and garden maintenance time.
A mine, like a tunnel, is a ready-made enclosed space with reliable wall insulation, which is very easy to isolate from the external environment and create a microclimate inside. Yes, there is a shortage of sunlight, but it is easy to replace it with ultraviolet lamps - mount just as much as you need. And such a recessed structure is perfectly protected from any vagaries of the weather.
The concept was named "deep farm", partly because it is planned to build them in long-abandoned places, on the outskirts of cities and towns. Instead of spending on the purchase of valuable acreage, a farm complex can be set up in an industrial zone or on a vacant lot, old mines are an ideal place. It is estimated that one such farm would consume energy like three typical UK households. But at the same time, work all year round, providing up to 10 crops, with a total weight of up to 80 tons.
All you need is to build racks with beds equipped with hydroponic systems inside the mine, to carry out lighting and heating. In theory, for this purpose it is even possible to use groundwater, which previously hindered the miners, rather than burning coal residues that have no commercial value to generate heat. Of course, there are difficulties with the maintenance of such vertical farms, but in the UK there are about 150, 000 closed mines - a huge field for experimentation. And the need for new food sources for a growing population is obvious.