Solar Thermal

Solex, from Fertilizer to Thermal Science

Solex, from Fertilizer to Thermal Science

Solex Thermal Science was born of necessity in the fertilizer industry. A fertilizer plant wanted to increase capacity, but didn’t have additional air emissions permits at the time. This was a problem because fertilizer processing – particularly the cooling stage – typically releases significant quantities of air pollutants like dust and other fine particles. Through ingenuity, the plant developed an industrial technology to cool the fertilizer without producing emissions, and while also reducing energy costs.

Solex’s indirect cooling technology passes material over a hollow plate, which contains a heat exchange fluid that indirectly cools the material through conduction. The process uses 90% less energy than traditional direct cooling and heating processes, resulting in significant cost savings. Solex’s technology also avoids air emissions because the material does not come into contact with air and allows the heat exchange fluid, usually water or thermal oil, to be reused.

Solex’s first sale was to a fertilizer plant in Alberta. Since then, Solex has evolved from its roots cooling fertilizer into a company that provides cooling, heating, and drying for a variety of products, including sugar, oilseeds, plastics, and coffee. Solex currently employs 63 people globally, with 38 of its staff in Calgary. The company has a number of installations in Alberta and operates in most other Canadian provinces as well as numerous countries around the world.

The applications for Solex’s technology continue to evolve. Given the company’s experience working with high temperature materials, it is now in the development stage of a solar thermal project to more efficiently convert sunlight to heat energy to generate power. Specifically, Solex is developing a heat exchanger that can transfer heat from high temperature solids to supercritical carbon dioxide, to be used as a fluid to spin turbines to generate electricity. The hope is to bring the cost of solar thermal from 12 cents/kWh down to 6 cents/kWh.

Solex is also able to store materials, including energy, at a high temperature for long periods of time. This allows Solex to dispatch the stored heat to power turbines when energy is needed and store the energy in the warm materials when it is not needed. When these heat storage capabilities are combined with solar thermal, it creates the potential for dispatchable renewable energy, addressing the energy storage challenge currently facing the renewable energy industry. Solex is building a small-scale system to test this concept, with plans to expand to a pilot scale in late 2018 or early 2019.

For more information on how to undertake your own clean tech project, check out the resources page.

Submit your new energy story here.

Canada’s First Concentrated Solar Thermal Plant


Canada’s first concentrated solar thermal plant

Medicine Hat is called the gas city, and for good reason. It sits on sizable natural gas reserves, which meant the city never suffered at budget time. In 2007, the city started down a path that should serve as a model to those lucky places that are endowed with fossil fuels.

The city’s one-megawatt concentrated solar thermal plant is the first of its kind in Canada. Row after row of large concave metal mirrors glow in the sun on the hill above the Trans-Canada Highway.

By focusing the sun’s rays onto a point, you can generate incredible amounts of heat. This project creates temperatures of 340 degrees Celsius. That heat is used to make steam, which spins a turbine and generates electricity.

"We had to reinvest, we had to diversify because all of our eggs were in that one basket"

It’s the farthest north a concentrated solar thermal project has ever been built, yet it makes sense in Medicine Hat. This is one of the sunniest cities in Canada, receiving more direct sunlight annually than Miami.

Concentrated solar thermal was the original renewable energy pacesetter. Massive projects were built in Spain, California and other sunny, arid places in the ‘80s and ‘90s. But solar photovoltaic modules, the familiar solar panels, have surpassed concentrated solar thermal. There are four gigawatts of installed concentrated solar thermal projects in the world but more than 300 gigawatts of installed solar PV.

The Medicine Hat project cost $9 million, with the funding split evenly between the city, the Province of Alberta and the Alberta Climate Change Emissions Management Corporation (CCEMC), the Province’s carbon technology mitigation fund. This installation works in concert with the city utility’s neighboring 204-megawatt natural gas fired power plant.

“We knew at the time we had to give back in some way. We had to reinvest, we had to diversify because all of our eggs were in that one basket, which was natural gas,” says Medicine Hat mayor Ted Clugston.

Read the full story on Green Energy Futures here

For more information on how to undertake your own renewables project, check out the resources page.

Submit your new energy story here.