Using landfills to help grow tomatoes? Brilliant!
Posted by by Colin Lyons, produce buyer
Wednesday, February 12, 2014
Local. Sustainable. Organic. As a produce buyer in Minnesota, these three adjectives are most often used to describe tomatoes grown only in the middle of August when it is 95 degrees and sunny. So why, in the dead of winter, am I talking about sustainable, organic and local tomatoes?
Just a few miles across the border in Lake Mills, Iowa, sits the Perfect Circle greenhouse. Since March 2008, Perfect Circle has been growing organic greenhouse tomatoes and distributing them to local retail outlets.
What makes Perfect Circle so special is what they use to help grow these organic tomatoes. I’ll touch on that in just a moment.
I took a short road trip down to Lake Mills (along with our produce quality assurance expert) to see just how special this operation really is. Lake Mills is a rather small town, and after a 30 second drive down Main Street, we were back on the prairie and headed straight toward the landfill.
Yes, I said it, the landfill. You see Perfect Circle is situated just across the street from a landfill. You might think that’s gross, but it’s good for many reasons:
1. Cheaper land = better tomato prices for you. Land next to a landfill is not the most sought after property. One thing that I have learned as a produce buyer is that the cost of land is a very large contributing factor to the cost of produce. This is especially true for organic farming as, generally speaking, more land is required to grow organic than the same yield of conventional produce. Both utilizing this rural space and growing in a high-yield-per-acre greenhouse is an excellent way to keep the cost of these organic tomatoes down.
2. Recycling harmful gases to make electricity. Perfect Circle has chosen to locate next to a landfill because landfills produce a large amount of methane gas. While this methane can be a damaging gas environmentally, if properly syphoned off it can be used as a fuel to power large generators that produce electricity.
Just outside the Perfect Circle greenhouse is exactly that: multiple generators producing electricity from landfill methane gases. They’re recycling the harmful gases from our waste.
3. Sustainable heat source. When we walked in their greenhouse from an outside temperature of 25 degrees, we were enveloped by wonderful warmth and the smell of a backyard garden in August. What was so amazing about the heat was its source.
You see, in the same way that a radiator and water pump keep your car engine cool, the large engines turning their greenhouse generators need to be cooled, too. To achieve this, cooler water is pumped into the engines and hot water exits. This hot water then travels to the greenhouse and into a heat exchanger where the heat energy transfers to another closed loop water system, which flows throughout the entire greenhouse. The greenhouse essentially acts a giant radiator, getting all its heat not from burning new fuel or electricity, but from the hot water pumping through these generator engines.
It is this setup that makes the Perfect Circle greenhouse so sustainable and such an intriguing business model. In the dead of winter, they can produce an amazing amount of product with minimal environmental impact.
Not only is Perfect Circle using interesting new methods to heat and power their greenhouse, they are also creating some of the best tasting tomatoes money can buy. After years of trying, learning and changing, their team has worked hard to bring us such a wholesome and delicious piece of fruit.
Pick some up today, and let me know what you think!