Power-To-X: Sunfire reports successful test run of co-electrolysis system of >500 hours; e-Crude demo targeted
16 January 2019
Sunfire GmbH reports the successful start-up and test run (> 500 hours) of a high-temperature co-electrolysis system at its Dresden site, beginning in November 2018. SUNFIRE-SYNLINK—a co-electrolyzer based on solid oxide cell (SOC) technology—enables the highly efficient production (a projected ~80% efficiency on an industrial scale) of synthesis gas in a single step using water, CO2 and green electricity.
Co-electrolysis reduces H2O and CO2 simultaneously; this significantly reduces the investment and operating costs for Power-to-X projects such as e-Crude and e-fuels.
Sunfire achieved the technological breakthrough within the framework of the Kopernikus project Power-to-X (03SFK2Q0), funded by the German Federal Ministry of Education and Research (BMBF), in conjunction with the Karlsruhe Institute of Technology (KIT).
The successfully running co-electrolysis plant (10 kilowatts DC, up to 4 Nm³/h synthesis gas) will be delivered to Karlsruhe in the next few weeks, where it will be combined with technologies from Climeworks (Direct Air Capture), INERATEC (Fischer-Tropsch Synthesis) and KIT (Hydrocracking) in a container to produce a self-sufficient facility.
The aim is to demonstrate the integrated production of e-Crude, a synthetic crude oil substitute, by the end of August 2019—the first in a 2-step process of this magnitude made possible by co-electrolysis.
Furthermore, on 1 January, Sunfire began the process of scaling-up the high-temperature co-electrolysis process to an industrial scale—initially with an input power of 150 kilowatts (DC)—as part of the “SynLink” project (03EIV031A) funded by the Federal Ministry of Economics and Energy.
This multipliable co-electrolysis module is to be used by Nordic Blue Crude, the Norwegian project partner. The first commercial plant is to be built there and will produce 10 million liters or 8,000 tonnes of the synthetic crude oil substitute e-Crude annually on the basis of 20 megawatts of input power.
Background: high temperature co-electrolysis. In previous power-to-liquids processes, two separate process steps were used to break water vapor down into its components—hydrogen and oxygen (electrolysis)—and to turn carbon dioxide into carbon monoxide (reverse water-gas-shift reaction).
With Sunfire’s co-electrolysis, hydrogen and carbon monoxide can be recovered in a single process step, significantly improving the efficiency of the overall process and lowering investment (CAPEX) and operating costs (OPEX).
In addition, the single-stage SUNFIRE-SYNLINK technology noticeably reduces the amount of space required.
The global demand for electrolysis technologies to produce green, renewable hydrogen is estimated at more than 3,000 gigawatts. Furthermore, many sectors, such as long-distance road transport, air or sea transport, require alternatives to fossil diesel and kerosene, which e-fuels can provide, thanks to their excellent transportability through existing infrastructures.
In addition to the production of fuels, synthesis gas attracts customers from a wide range of industries, such as the chemical industry, plastics production or the cosmetics sector.
Sunfire recently acquired a new lead investor and technology partner in Paul Wurth, a leading global mechanical and plant engineering company for the metals industry. The investment round, which involved former investors, yielded an additional €25 million in capital. Sunfire will use the money to implement commercial multi-megawatt electrolysis and Power-to-X projects.
Resources
Yun Zheng, Jianchen Wang, Bo Yu, Wenqiang Zhang, Jing Chen, Jinli Qiao and Jiujun Zhang (2017) “A review of high temperature co-electrolysis of H2O and CO2 to produce sustainable fuels using solid oxide electrolysis cells (SOECs): advanced materials and technology,” Chemical Society Reviews doi: 10.1039/C6CS00403B
In order for this technology to contribute significantly to decarbonization the CO2 must be directly extracted from the atmosphere. Making carbon do double duty (e.g. using CO2 captured from fossil fuel generators or from cement making) would decrease CO2 emissions per unit of economic output but would not stop the flow of fossil carbon into the atmosphere.
Posted by: Roger Brown | 16 January 2019 at 08:12 AM
Crude oil has on the order of 42-47 MJ of energy per kg (depending on grade, heavier will be less). Assuming that this syncrude is the equivalent of light sweet, it will be toward the 47 MJ end.
8 million kg * 47 MJ/kg is 376 TJ energy of product. 20 MW * 3600 s/hr * 8766 hr/yr = 631 TJ. The net process will be on the order of 59% efficient (before losses in refining). Could be worse, but given the downstream inefficiencies, batteries are going to be a much more efficient way of converting electricity into motion.
Posted by: Engineer-Poet | 16 January 2019 at 09:52 AM
Practically we can only work with proven technologies which can also offer us a place from were the future can be seen as incremental.
E.P.'s number magic in keeping with the laws of physics is above my pay grade but if rule of thumb and context were the only tools available those numbers would accurately centre the bullseye.
It is also understood that generally hydrocarbon fuels are unlikely to beat 45% thermal efficiency at the point of use while battery technology with over three X that efficiency is not yet a viable option for commercial aircraft shipping or long distance locomotive.
While the report claims 80% efficiency in 'some context' , realistically it may offer slightly better efficiency than comparable H2 by electrolysis process and may offer substantial CO2 reductions over fossil oil if CO2 is recycled.
Any which way until substantial amounts of 'green electricity' is regularly available it does not scale.
Rather than be pessimistic when facing this reality, it shows a clear rational to
build big on -e.g. wind and solar with the understanding that there will full utilisation albeit at lower ranking efficiencies.
Posted by: Arnold | 16 January 2019 at 02:23 PM
The attractiveness of synthetic hydrocarbons vis a vis battery storage of renewable energy is easy transportability within the existing infrastructure. For example if you locate solar energy production in equatorial deserts with 12 to 18 hour of storage then the electrolyzers and chemical processing facilities could be used with high capacity factors, and the resulting hydrocarbons could be moved around the world using existing transport infrastructure. Of course ubiquitous nuclear power would obviate the need for such a scheme, but such a power infrastructure does not appear imminent. Even in China where the government does not have to worry about an anti-nuclear lobby I do not detect any sign of convergence on a predominantly nuclear future.
Posted by: Roger Brown | 16 January 2019 at 02:29 PM
I believe we've had Achates come in at substantially over 50% and CCGTs exceed 60%, albeit on a lower heating value basis (not counting the lost heat of condensation of the water in the exhaust).
The real attraction of this technology isn't CO2 reduction, but storage. Hydrogen is very difficult to handle and store compared to even methane. But syncrude? You can pile up syncrude in tanks or even salt domes and probably leave it for years. This scheme is supposed to be the answer to even seasonal deficits of "renewables". However, the round-trip efficiency of 30% or less even before the energy cost of CO2 capture is included is going to make that a lot less attractive.
Posted by: Engineer-Poet | 16 January 2019 at 05:13 PM
Well, that and fungibility within the current system. This allows plenty of fraud; there's no way for a consumer to tell the difference between fuel made from atmospheric carbon and fuel made from crude oil without testing the carbon isotope ratios.
Posted by: Engineer-Poet | 16 January 2019 at 05:13 PM
@Roger: they do direct air capture (climeworks).
Even if no liquid organic fuel is needed in the future, we will still need gigatons of plastics.
Wheen cheap green energy will be abundant, it will be obvious to make them locally from air. Certainly for countries with no domestic crude production, and with a correct carbon price.
Posted by: Alain | 17 January 2019 at 12:56 AM
We aren't there yet, but intermediate temperature SOFC's offer the possibility of using hydrocarbons with far more than 45% efficiency on board.
They can hit in excess of 75%.
The unrivalled ease of carrying and the compactness etc of synthetic hydrocarbons are not to be lightly discounted.
Posted by: Davemart | 17 January 2019 at 01:13 AM
H2 is also very prone to fraud, extracting hydrogen from natural gas does nothing for reducing CO2, so this is the same for liquid fuels from green energy. If the fraud aspect can be managed (or somehow synfuels get cheaper than fossil), this could be a fantastic solution for trucks, since it doesn't require a new fueling infrastructure as for H2, or massive grid upgrades as for battery trucks.
Posted by: Opbrid | 17 January 2019 at 01:20 AM
At times, it is really sickening to see to what excesses wishful thinking can lead to.
Presently, there are two viable methods of electrolysis that are acceptable for an emissions-neutral process; both are based on the implementation of renewable energy.
Splitting H2O via electrolysis (at normal temperature) to produce Hydrogen and Oxygen is an established procedure. The other more efficient method is high temperature electrolysis. However, the high temperature is not achieved with a magic wand and the overall system efficiency is less than the first mentioned method. As already mentioned in one of the preceding comments, it is exceedingly difficult to store Hydrogen without suffering excruciating losses; this applies to both methods.
Posted by: yoatmon | 17 January 2019 at 03:00 AM
I wish to recall to all readers' minds that: neither matter nor energy can be created or destroyed it can only be converted from one form to the other. Or even better, Einstein's equation - E=mc² - clearly explains that everything is energy albeit matter a different form of energy. I.O.W . in our universe you won't get anything for nothing. Personally, my bet is on those batteries in 5 to 10 years time that will beat any fossil fuel dream anyone can come up with. My credo is efficiency and emissions neutrality.
Posted by: yoatmon | 17 January 2019 at 03:01 AM
We currently have no efficient way to store electricity as anything more energy-dense than the energy of chemical bonds.
Converting energy to mass as a storage medium means converting mass to energy on the return trip. I'd be very wary of anything that could do this, because it would make a frighteningly good bomb.
Posted by: Engineer-Poet | 17 January 2019 at 03:09 AM
That is true as far as batteries are concerned but both, batteries and super caps, are improving day by day. Super caps do not store energy via a chemical reaction and Graphene has far more up its sleeve than is visible to us momentarily.
Posted by: yoatmon | 17 January 2019 at 07:11 AM
Which is why they have far lower energy density than batteries.
Posted by: Engineer-Poet | 17 January 2019 at 10:51 AM
Efficiencies for the heat engines refers to optimum flow. Outside of those parameters including at idle they can lose to 100%.
While there exist strategies that reduce these effects they can't eliminate it.
If heat is desired the numbers improve.
Electric machines are closer to linear efficiency at varying speeds.
Posted by: Arnold | 17 January 2019 at 02:04 PM
@ EP
https://www.graphene-info.com/graphene-supercapacitors
Posted by: yoatmon | 21 January 2019 at 04:00 AM
@yoatmon: from your source:
There's a price for the power density and cycle life of ultracaps, and that's energy density. They do best in the deci-seconds to handful-of-minutes energy storage segment.
Posted by: Engineer-Poet | 21 January 2019 at 02:57 PM