Reaching Net Zero: How Cambridge-based company Extract Energy pioneered a way to turn waste heat into clean electricity
This is part of a series highlighting Canadian companies striving to quickly reduce greenhouse gas emissions.
All over the world, every second of the day and every time fossil fuels are burned, a tremendous amount of heat is generated and ultimately pumped, unused, into the atmosphere. You can see it in the steam gushing out of power plants, smell it in the back of the fridge, watch it practically radiate on your overworked laptop. By some estimates, up to 65% of the energy we consume is lost as low-quality waste heat. Traditionally, such heat is unusable and most industries use liquids, air conditioning or dry coolers to expel it.
In an age when we need to make better use of all the energy at our disposal, such processes seem both backward and, well, unnecessary.
But what if that heat, all those many gigawatts of wasted energy, could be captured and converted into something useful, like zero-emission electricity? It is the alchemical vision of Extract energy, the spin-off company of Smarter Alloys Inc. based in Cambridge, Ontario. Its ingenious thermal engine transforms low-quality waste heat into electricity. Whether connected to a distillery or a data center, it can provide clean electricity, lower cooling costs, and dramatically reduce greenhouse gas emissions.
Other technologies are already recovering heat, including Rankine motors, which have been used in European power plants for more than a decade. But Extract Energy CEO Ibraheem Khan says that on a large scale, his heat engine will produce much cheaper electricity and reduce emissions even more. There are about 68 terawatt hours of untapped energy in waste heat produced around the world each year, says Khan. It aims to reach 25 percent of this market.
“Our target market adoption rate is pretty aggressive,” he says. Assuming the adoption rate is reached, by 2050, Khan estimates that his company will be able to reduce GHG emissions by five gigatonnes per year, or about 14% of annual global emissions.
“The global demand for energy is booming,” says journalist Nicola Jones in Yale Environment 360, a publication of the Yale School of the Environment. “And every part of the waste heat recycled into energy saves fuel – often fossil fuels – by not doing the same job. “
At the heart of Extract Energy’s engine are unique alloys, the main one being a mixture of nickel and titanium called Nitinol, which are processed to optimize their power output. These so-called shape memory alloys are super elastic and infinitely changeable: once bent or manipulated, they return to their original shape when heated.
Describing such a high-tech material is tricky, but think about the softening of fresh pasta when in boiling water. Only here the process is reversed, with individual sections of pasta that can then be shaped in different ways and exert tremendous force. Extract Energy uses wires or springs made of Nitinol (and other proprietary alloys) that can be “programmed” by high power laser pulses to expand and contract when submerged and withdrawn from a hot liquid. Springs or wires convert this heat into kinetic motion which then drives a generator. The amount of force created by these alloys is mind-boggling – spill hot coffee, for example, on a single spring small enough to fit in your hand and it can produce enough power to lift a train car.
Khan, 39, a materials engineer, designed the technology while he was studying for his doctorate at the University of Waterloo. While playing with Nitinol one evening in 2009, he noticed that the material could be reshaped at different temperatures and also remember these different shapes. At first Khan thought there was a flaw in the hardware, but after a few weeks the impact of the discovery hit him. “I realized that we could take a material, give it the ability to transform into a number of different shapes, and basically make it work like a machine,” says Khan. Not wanting this discovery to simply end up buried in an academic article, he set out to develop commercial applications for it, co-founding Smarter Alloys in 2010.
Khan’s wife is a dentist and the first app he developed was a precision-tuned archwire for braces that applied specific pressure to individual teeth. Over time, the company has also created applications for the medical, automotive, aerospace and clean energy sectors.
Last January, Smarter Alloys moved into a sprawling complex in an industrial park in Cambridge. While its office spaces still seem a bit unfinished, the real action takes place behind the building, in the laboratories and manufacturing areas that house many specialized devices: electron microscopes, electric discharge machines, scanning calorimeters. differential. A large boiler and dry cooler, designed to mimic the operations of an industrial plant, occupies a significant portion of a spacious high-ceiling garage.
Outside, amid a graveyard of abandoned machinery and materials, is the first prototype of Extract Energy. It was first used successfully in an industrial trial in Calgary Last Spike Brewery, where wastewater from the beer-making process was used to generate electricity (it was able to produce peak powers of 500 watts). It was a surprisingly humble piece of metal, plexiglass, gears and belts, the size of a tandem bicycle. At each end, rows of alloy coils were visible, resembling springs you might see in a carburetor.
Inside the garage, however, is a much more formidable version of the same heat engine, still under construction. Its charging frame, when completed, will contain enough alloy wires to produce 100 kilowatts of power. “We are aiming for megawatts of electricity,” Khan said. “Which is really going to have an impact.”
Extract Energy’s applications, according to Khan, are “endless,” but from an environmental perspective, it focuses on a few different areas, including geothermal power and data centers. For example, the endless geothermal heat found in orphaned oil wells (created by radioactive decay in the earth), could theoretically be harnessed forever. In a future without fossil fuels, power plants could be located next to or above these holes.
Conventional data centers, on the other hand, are, in Khan’s words, “glorified literally massive heaters.” A small portion of the energy in them is actually used for computing, and the rest is waste heat, with companies like Amazon using even more energy to cool and move that heat.
Smarter Alloys has partnered with another cutting-edge Calgary-based startup Denvr Dataworks, which completely redesigned the data center. The two centers that Denvr is currently building are compact, modular spaces densely populated with extremely fast and energy-efficient computers, all cooled using mineral oil rather than conventional air conditioning. Denvr will power its data centers with renewable energy, and this hot mineral oil will directly power the Extract Energy heat engine, whose electricity will then be fed back to the data center.
“Our goal with Smarter Alloys is to have a data center by early 2022 where operations will be carbon neutral,” said Dave King, CEO of Denvr. “This will be, as far as we know, the world premiere.” King says his company is about five years ahead in terms of technology, but all other data centers will need to follow suit. While large companies are generally more reluctant to try new technologies, this method of capturing waste heat would greatly help multinationals meet their net zero commitments.
“We are confident this will become the norm within a decade,” King said. “Once your heat is liquid, you can do things with it. We could heat a greenhouse. When it’s air, you’re just blowing heat through the chimney and killing the planet.
Khan echoes that sentiment when he talks about what makes him and his company tick. Even with all of the various innovations and products that Smarter Alloys has created and are in development, around 80% of its resources and brainpower are devoted to energy extraction and its potential impact on the environment.
“You sort of work for your children,” Khan says. “If we can apply this science to one of the biggest problems we have on Earth, it will be the most impactful thing we can do for our children and their children. This is one way to help reduce the risk of climate change they will experience.
Disclaimer This content was produced in partnership and therefore may not meet the standards of impartial or independent journalism.