Could Ottawa’s clean energy tech cluster be a leader in large-scale atmospheric heat capture and conversion technology?
We are witnessing a steady stream of media reports about global atmospheric warming, which is widely attributed to greenhouse gas (GHG) emissions from fossil fuels. To counter this global warming, there has been much governmental emissions-related policy-making, and accelerated development of clean technologies such as renewable energy from wind, water and solar, plus GHG emissions reductions at source, and carbon dioxide capture, utilization and/or storage. But if the atmosphere is becoming too hot, why is there not more discussion about recapturing and recycling the atmospheric heat itself? In this blog piece, I am going to try to make the case that Ottawa’s clean energy tech cluster could take a leading role in the development of atmospheric heat capture and conversion technology as part of humanity’s campaign to counter global warming.
The European Union’s Copernicus Climate Change Service has recently announced that the world has just experienced its first 12-month spell of atmospheric temperatures over 1.5°C above the pre-fossil fuel 1850-1900 norm, which has been the consensus threshold for triggering more severe environmental consequences than what we’ve witnessed already. Even worse, the pace of warming seems to be quickening, with almost 1°C of this temperature increase coming within the last 25 years alone.
GHG emissions such as carbon dioxide and methane are commonly named as the primary villains for this observed global warming. The prominent role of fossil fuel combustion in generating such GHG emissions has consequently led to a broad portfolio of anti-fossil fuel societal responses, including widespread calls for the end of fossil fuel consumption, development of carbon-related policies and taxes, rapid development and deployment of renewable energy technologies, and investment in carbon capture, utilization and/or sequestration (CCUS) technologies, and so on.
Unfortunately, the consumption of oil and gas is continuing to climb, as are their associated emissions, and many forecasts predict a temperature increase of 2°C or more before the end of the century without even more aggressive counter-measures. Thus, regrettably, it appears that society’s collective actions so far to discourage consumption of fossil fuels, and to reduce and/or capture their GHG emissions, may not produce enough results, and the results may not be fast enough, to avert significantly increasing harm from global warming.
But is there another way of seeking solutions to address this grim outlook, that might allow us to more effectively and more quickly subdue or reduce global warming? Yes, I do believe that there is another global warming villain besides GHG emissions that warrants more of our attention; and at the same time, ironically, I believe that villain could potentially be a timely saviour.
So what is this other global warming villain/saviour? My proposal may sound simplistic, but bear with me. I am suggesting that the other important villain is the heat itself that humans have been pouring into the atmosphere (“anthropogenic heat”) primarily from our consumption of all forms of energy, plus other human-related contributions such as radiation from urban infrastructure (aka “urban heat islands”). But how could this heat also become our saviour? Let me try to present my case.
Humanity currently consumes approximately 600. exajoules (EJ) of energy per year, growing at about three per cent per year. This is energy derived from all sources such as fossil fuels, hydrogen fuel cells, wind turbines, hydro dams, nuclear power plants, solar panels, geothermal heat and/or power plants, etc. Within minutes, hours or days of consumption, almost all of this consumed energy ends up as residual heat in the atmosphere, except for a small fraction (e.g., from visible light) that escapes directly into space.
So what? Does such anthropogenic heat make a significant contribution to global warming? The proportion of the observed atmospheric temperature increase attributable to anthropogenic heat is a matter of some debate (to put it mildly) in the scientific community, ranging from less than 10 per cent to “at least half”. But given that some 6000 EJ is required to raise the earth’s atmospheric temperature by 1°C, the annual 600 EJ of anthropogenic heat from energy consumption, let alone the other anthropogenic heat elements, does seem to be large enough to make a very concerning contribution to global warming.
If anthropogenic heat is indeed a significant and growing contributor to global warming, then there are at least two important implications. First, it is possible that no amount of GHG emission reduction is going to stop global warming entirely. That is, even if we achieve net-zero GHG emissions, human production and consumption of all forms of energy will continue to discharge heat into the atmosphere at increasing rates compared to what we’re currently discharging, plausibly resulting in continued global warming.
Second, to truly limit or reduce global warming in an effective and timely fashion, we must therefore squarely confront the most obvious problem, which is the heat in the air. All of the energy that humanity needs exists as heat in the air all around us, and it’s accessible 24/7, independent of wind, sun and seasonal conditions – if only we can figure out how to capture it and recycle and/or convert it on a massive and cost-effective scale.
This does not strike me as impossible, as we are already proficient at harvesting some forms of atmospheric energy. For example, we can convert the kinetic energy of the wind into electrical energy via large wind turbines, and we have become very proficient at shifting atmospheric heat from one location to another with air source heat pumps. But how can we get even better at capturing and/or recycling atmospheric heat, and at a much larger scale?
As one potentially fruitful R&D vector, I’d suggest investigation of direct conversion of atmospheric heat into electricity. Nature already accomplishes this very effectively with lightning, using heat-related convective turbulence in the upper atmosphere to create charge imbalances followed by dramatic electrical discharge. But, so far, humanity’s capability to convert atmospheric heat directly to electricity (let’s call this AH2E technology) is nowhere close to this.
Yes, humanity has developed some capability to convert some non-atmospheric sources of heat to electricity, such as using steam-driven turbines in gas-fired, coal-fired, nuclear, or geothermal power plants to generate substantial quantities of electricity. Furthermore, we can use heat differentials in small solid state thermoelectric generators (TEGs) to generate tiny amounts of electricity, and some advances are being made with small-scale thermophotovoltaic devices.
However, as far as I’ve been able to discern, there are no AH2E technologies either in-use or in development, especially not on the massive scale required. Perhaps this is a moment where Ottawa’s clean energy technological ingenuity can step up and pioneer the AH2E technology that humanity must have to fully confront and subdue the threat of global warming?
There is actually a significant pool of clean energy engineering expertise in Ottawa that when viewed in totality could be accurately called a “hub” or “cluster”. In the university sector, we have Carleton University’s Sustainable Energy Research Centre, the University of Ottawa’s research cluster on Renewable Energy Technology and Control, and uOttawa Faculty of Engineering’s research cluster on Sustainable and Resilient Infrastructure. In the federal government, we have NRCan’s CanmetEnergy Research Centre for Renewable Energy, and NRC’s Clean Energy Innovation Research Centre. Finally, in the corporate sector, we have well-established clean energy companies such as Thermal Energy International, Iogen, and Omni Conversion Technologies. Given this pool of engineering expertise, and with sufficient initial R&D funding, in my view Ottawa could indeed take a leading global role in developing the essential, but currently overlooked, AH2E technology.
To be clear, I am not suggesting that we stop our efforts to decrease and/or capture GHG emissions. Let’s continue those efforts, as there is no doubt that we must do so. However, we need a wide variety of tools to counter global warming, and the successful development of AH2E technologies would be an additional and vital tool for the toolbox.
In summary, yes, in my view there is another global warming villain besides GHG emissions, namely the anthropogenic heat released into the atmosphere from humanity’s expansive consumption of energy in all forms. This anthropogenic heat is large and ever-growing, seemingly enough to continue to significantly warm the planet even if all GHG emissions are stopped. But ironically, this anthropogenic heat also has the potential to be a timely saviour, and in my view, Ottawa’s clean energy engineering cluster is well positioned to take a lead role in developing large-scale atmospheric heat capture and conversion technology, perhaps with particular focus on atmospheric-heat-to-electricity.
By: David Large, president of Clean Planet Systems Inc.
