US based Heliogen this week got an enormous amount of coverage, so much so the phone will be ringing off the hook. It was kind of a company launch, out of stealth, but at the same time it was supposed to be an investment round – the amount of money was not specified, but it was intimated that this was go to market money – we’re having none of it, the idea is in its infancy and needs considerable development.
In the end it is just another Concentrated Solar Power company, but what has people writing about it is the fact that Bill Gates has invested in it, but as we have pointed out in the past, a smart guy from an older technology war investing in renewables is just another guy with money. The Gates name gets people to put on their kid gloves and write it up nice, but as they say “the proof of the renewable is in the heating.”
First let’s look at the unique element of its announcement. Heliogen applied some machine vision to the process of lining up the mirrors – for those who don’t know, most CSP works on a predictive process – lots of mirrors aimed to reflect sunlight into a single thermal solar panel based on where the sun should be, and the last orientation of the mirrors. Usually the heat from the output is used to drive a steam turbine and create electricity, or the steam is used to heat molten salt to around 600 degrees Celsius as a form of storage.
There have been numerous experiments to go beyond this 600 degree temperature, and Helogen is just another of them – because lining up the mirrors precisely in real time, needs a real time feedback loop, built around a camera. Of course the camera has to make some assumptions because it cannot be at the center of the beam of light, because it would melt. Instead it is lined up with the halo of the sun’s image.
The first time the Heliogen team tried this successfully, the temperature went off the charts to 1,000 degrees. However once you have achieved this you have the problem of how do you harness that temperature? If you use a steam turbine to turn it into electricity, you have lost the point really of creating such a high temperature stream without burning fossil fuels.
The company points out that it can be used as a heat source for the production of cement, steel, and petrochemicals. That is potentially true, but this will be a long way off – perhaps 10 to 12 years. First it has to either take the mountain (industrial process) to Mohammed (the CSP) or the other way around. And this kind of CSP will only work in a limited area of the globe close to the tropics, where there is uninterrupted intense sunlight. And all that mirror alignment means it can’t be done on the sea, so it has to have a piece of desert to itself, and you have to move your cement factory there.
The company admits that initially it was working on creating hydrogen from water, which requires a temperature of 800 degrees in the present of a catalyst, and the creation of Syngas, used for producing Ammonia or Methanol at around the same temperature.
Even then the problem persists that if a rogue piece of cloud gets in the way the temperature may fall and disturb the process. It also means no 24 hour working, at a plant as the sun tends to go in at night. The CEO Bill Gross talks about later using volcanic rock as a storage medium for the high temperature – and instances of this right now only go up to 600 degrees again, so we are back to looking for a new storage medium or a different type of rock that can sustain a higher temperature. More inventing required.
But the creation of hydrogen has been passed off as something that can be done intermittently, such as at sea powered by wind farms, so perhaps scaling hydrogen creation is a possibility – but mostly it will have to be in the tropics.
We cannot see it being used at scale on today’s cement factories which are supposed to account for 7% of global CO2 emissions, until all of these problems are solved, but this was the main point of the announcement.
The CEO says that Heliogen has a roadmap for temperatures up to 1,500 degrees. Well you need to heat steam to around 3,000 degrees for oxygen and hydrogen to be created through the breaking of the chemical bonds, and for this to happen on its own, so he doesn’t mean that, he means electrolysis facilitated by high temperature, which is 800 degrees.
But the CEO Gross is the founder of Idealabs, and it just so happens that his last start up in renewables was Energy Vault, which also came out of Idealabs and which took huge funding from Softbank. Are we seeing a connection here? Some engineers from Caltech and MIT have come in the door, with an idea, and Gross has said “you need a to CEO – me,” followed swiftly by “I can get you money from my rich mates such as Softbank or Bill Gates.”
But all of us are asked to make the connection between Gate’s supposed genius instead of his money, and this enhances the fundamental idea of high temperature CSP in our minds. It is a good idea, but it has been done before, for instance at the Sandia National Laboratories as far back as 2013 on a project called Solar Two, built in the Mojave Desert, which led to the ideas behind the “Solar Tres Power Tower,” in Spain.
Heliogen also says it is now working with Parsons Corp big in defense and infrastructure markets, which is looking for the technology’s first customer. Other investors include VC firm Neotribe and Patrick Soon-Shiong, a Los Angeles-based individual investor.