A Fish Farm Grows Thanks to Combined Heat & Power

Amid an endless horizon of irrigated cropland, in a hot, arid corner of south-western Alberta, you think it must be a mirage.

But no.

There it is: a thriving, large-scale, landlocked tropical fish farm.

Current Prairie Fisherman Corp. is owned and operated by father-son team Klaas and Justin Den Toom.

It wasn’t always a fish farm. The Den Tooms started out raising hogs on the site, in 2002. Then in 2008 they began farming tilapia and barramundi – native to Africa and Australia, they’re mild tasting, warm-water fish in demand by restaurants in Calgary and Vancouver.

After years of building trust and a roster of steady customers in the restaurant industry, the Den Tooms realized there was an opportunity to provide additional value to their customers. By growing and diversifying the farm yet again, they could put the fish waste to work as plant fertilizer: In addition to fish, the Den Tooms could provide restaurateurs with a reliable and familiar source of specialty vegetables, and attractively boost their bottom line at the same time.

The business model was good for both the farm and the Den Tooms’ long-time customers, but the challenges in execution mirrored those of every farmer. The biggest operational costs – namely the energy to power their operation and the cost of feed (in this farm’s case, CO2 to boost growth and yield) – were serious management concerns.

The planned greenhouse was 100,000 square-feet in size. It would need to be warmed in the winter and cooled in the summer, while the waste from the fish would have to be filtered for use on the plants. Each of these processes required power.

To make this ambitious venture cost-effective, the Den Tooms needed to accurately forecast and control their power, heating and cooling costs. Because the farm is located at the end of the power line, in a rural area prone to severe cold, wind and ice in the winter and blistering heat in the summer, they needed to ensure they could affordably grow plants year-round in this challenging environment without interruption. They also needed to budget the annual cost of carbon dioxide (CO2) necessary to support and accelerate the growth of the plants.

The Solution

When the Den Tooms were introduced to Tedom’s combined heat and power (CHP) or co-generation units, the way forward became clear.

There are many advantages to the Tedom CHP model, but the most significant was that complementary technologies could be added to make ‘quad’ generation technology: power, heating, cooling and food-grade CO2 recovery.

By installing three Tedom Cento T200 200kW units, the total quad-generation solution solved multiple costly issues for the farm at once. The units delivered power cheaply, because they run on natural gas and because there was no need to pay for additional power distribution or transportation. The waste heat produced would be a free source of warmth for the farm, but it could also cool air when put through an absorption chiller. Finally, because the units can capture the CO2 by-product of generating power, clean it of pollutants and put it to essential use in the greenhouse, it could improve crop yield by as much as one-third.

 Return on Investment

The Den Tooms estimate that by eliminating the need to purchase CO2 alone, they’ll save as much as $150,000/year.

By powering their quad-generation solution with economical natural gas, “We’re now talking about a fuel source that is upwards of 85 per cent efficient,” says Justin Den Toom. “The results have been better than we’d even hoped.”

Today the Den Tooms’ have year-round, uninterrupted growing, unaffected by challenging exterior weather conditions. Energy and heating costs are controlled and predictable, while fish waste is filtered and used as fertilizer and excess C02 is captured and likewise “fed” to the plants.

Tedom units are an independent, cost-effective and reliable power source that’s specifically designed to run 24/7 at full power. With an average 20-year life-span, they’re designed to last too, which is a good thing:

In an ocean of farmland, the Current Prairie Fisherman Corp. aims to be the go-to supplier of tropical fish and vegetables to restauranteurs in western Canada, for a generation to come. With the help of their modified Tedom CHP units, the Den Tooms will make it so.