Carbon Commentary newsletter

This newsletter has been dormant for the last months. I’ll restart it and try to write it every few weeks, covering what seem to me to be the most interesting news stories in the energy transition. Suggestions for topics to cover are always extremely welcome.

1, Low carbon industrial plastics. Korean manufacturer Kolon Industries said it will launch the world’s first low carbon engineering plastic. The product will be made from methanol generated from renewable hydrogen and captured carbon dioxide. The plastic – POM or polyoxymethylene – has a global demand of about 2 million tonnes a year, a tiny fraction of the world’s production of about 450 million tonnes. But this is an important step because methanol is one of the two or three most important precursor compounds in the world chemical industry. The commercialisation of this new product, firstly as a component in medical devices, will help reduce the methanol price premium from using low carbon sources.

2, Costs of the heatwaves. France produced an estimate of the cost of the heatwaves this summer. The figure of €10-15 billion, or about 0.25%-0.4% of GDP, includes wildfires and crop yield reductions. The government admitted this figure was only approximate and it will rise as the heat continues. And the number doesn’t include the cost of reduced human contentment as a result of the excess temperatures. But it stands in contrast the estimates of the additional investment costs needed to meet France’s energy transition objectives by 2030 at between €63 and €110 billion a year.

3, The first flight with fully sustainable aviation fuel (e-SAF). We know we can make SAF from biological sources and perhaps 1% of all aviation fuel in 2026 will come from this route. Expansion is slow, with only about one quarter of global manufacturing capacity used. Biological SAF is currently twice as expensive as conventional aviation fuel, even at today’s high levels. Rather than being made from biological sources, e-SAF is made from green hydrogen and captured CO2. What may have been the world’s first passenger flight using e-SAF occurred in early August on a flight between two cities in Texas. The fuel came from Infinium Energy, which operates one of the few commercial scale power-to-liquids plant. Infinium’s fuels probably sells for about five times current aviation kerosene prices, partly because of the continuing high cost of green hydrogen. Another company, Lydian, recently raised cash from Breakthrough Ventures to develop a lower cost route to making liquid fuels, emphasising the importance of using flexible technologies that can be run to make hydrogen when the electricity price is low.

4, ‘Calcium looping’ for direct air capture (DAC). Heating calcium carbonate, as in the process in which Portland cement is made, drives off a dense stream of CO2 that can be captured and stored. The remaining lime (CaO) may be then be processed so that it extracts CO2 from the air, reforming the calcium carbonate. This DAC process is relatively simple and has been pursued by the UK company Origen for some years. A new study confirms that the process may be an efficient and relatively cheap means of extracting net CO2 from the atmosphere. That conclusion depends on the price of electricity used to initially heat the calcium carbonate. The process is best suited to high humidity countries where alternative DAC technologies, such as amine adsorption, would be relatively less effective.

5, Green hydrogen from photocatalysis. Sparc Hydrogen in Australia said it would use modules from US company Sun Hydrogen to build its reactors that take in concentrated solar energy to split water into oxygen and hydrogen using catalysts. The process therefore does not require electrolysers. Sun Hydrogen’s products now offer a 10% conversion efficiency of solar energy into hydrogen, a level widely regarded as sufficient to make photocatalysis cost competitive with electrolysis. The ultimate target may be a conversion efficiency as high as 30%, at which level hydrogen production in the sunniest countries may entirely move to this route, rather than electrolysis.

6, Saudi Arabia green hydrogen. Even as European projects get cancelled and hydrogen deployment runs well behind schedule, Saudi Arabia reported that the Neom 2.2 GW green hydrogen and ammonia plant had begun commissioning with production of up to 600 tonnes H2 per day starting in 2027.

7, Iron-air batteries. Form Energy in the US is the leader in the development of grid-scale batteries that charge and discharge electricity by turning iron into iron oxide (‘rust’) and back again. Safe, simple and using no scarce materials. It raised a further $750m from a wide spectrum of investors. The company already has an order book of around 80 GWh, or about five times the total installed battery capacity in the UK today. Form’s first product will be a 100 hour discharge battery, configured to meet typical long duration storage needs in sunny markets such as California. (It claims the discharge time can be altered substantially up and down). Form’s products are thought to be very inexpensive at around $30-35 per kWh, or less than half the cost of LFP batteries. However the round trip efficiency is likely to be around 50%, far lower than lithium-based equivalents. And the fresh water needs are huge, amounting to about 50 tonnes of water per charging cycle for each MW of capacity. This is not a technology for dry countries.

8, Mixed plastics to hydrogen. The separation of the different plastics in a waste stream is difficult and expensive. The world may therefore probably have to find ways of processing wastes composed of multiple different types of plastics. A research study reported a new potential route to extracting value from a mixture of PET, polypropylene and polyethylene, which together form a very large fraction of consumer waste. The process can also cope with labels, printing inks and adhesives that characterise household throwaways. Sodium hydroxide is added to the plastic mix and heat applied, producing hydrogen at a purity above 90% alongside stable carbonates. This is not perfect circularity by any means but may be the cheapest and most easily implementable form of plastics recycling.

9, AMOC. The Atlantic Meridional Overturning Circulation (AMOC ) keeps north-west Europe relatively warm in winter. Decreasing ocean water salinity as a result of Artic ice melting in rising temperatures threatens to weaken this ocean flow, and may already be doing so. New research adds a powerful element to our understanding of whether AMOC collapse is likely in the foreseeable future. The work demonstrates that it may not be the absolute level of temperature rise that is important. Rather it is speed of temperature change that matters. So slowing down the rate of GHG additions to the atmosphere may be sufficient to avert the very serious effects of AMOC collapse in north-west Europe. The challenge is to dramatically reduce the GHG additions within the next few years so as to slow the rate of temperature change. The researchers suggest a slow rise of 0.5 parts per million per year in atmospheric CO2 levels is likely to keep the AMOC stable even at much higher temperatures than today. Current GHG additions run at about 2.5 parts per million per year so we have a steep hill to climb.

10, Electric trucks. Electric trucks accounted for over 30% of China sales in 2025, with volumes more than double those of 2024. Diesel use is said to be falling. China was more than 90% of total global demand for electric commercial vehicles in 2025 but rapid growth is spreading into other countries. Exports of e-trucks rose to over 16,000 in the four months to June, with over half going to other Asian countries where the rise in the price of diesel has been particularly sharp.

11, UK plug in solar. Installation of plug-in solar will be allowed in the UK in ten days time. However none of the small number of solar inverters that have applied for permission to connect has gained approval from the regulator ENA. This is an astonishing situation and everybody installing plug-in solar will be breaching connection rules. Our work on these kits suggests some inverters will frequently trip out because of the typically higher voltages on local distribution networks in the UK compared to the rest of Europe. The inverters are not designed for the 250+ volts seen on some UK connections when nearby solar rooftops are producing large amounts of electricity. (Thanks very much to Nikos Dimitriadis and Adrian Arbib for their excellent work on this topic).