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California and Sweden to Cooperate on Biomethane and Renewable Fuels

California and the Kingdom of Sweden have finalized a memorandum of understanding (MOU) to cooperate with one another and the industry to develop bioenergy, particularly biomethane.

Representatives from both governments signed the MOU in Stockholm this month identifying how the two states can benefit from enhanced information-sharing and interaction to develop bioenergy for transportation fuels and other uses.

Through strong cooperation between its industry and government, Sweden is showing the world how bioenergy can be developed in a cost-effective manner that benefits its economy and environment. This MOU will provide a basis for intensified collaboration between our states to help California develop a thriving bioenergy industry.

—Joe Desmond, Resources Agency Undersecretary for Energy Affairs

Sweden is a global leader in converting biowaste derived from agricultural material and residues into usable biomethane. The gas is used to generate electricity, residential heating, or as a transportation fuel. Biomass sources make up 45% of Sweden’s methane, and the country’s biomethane industry has been growing at an annual rate of around 20% over the last five years.

Officials signed the MOU after a tour of Swedish biomethane facilities by a delegation of California business and government leaders. Led by Desmond and California Energy Commissioner Jim Boyd, the delegation included leaders from the state’s dairy and ranching industries, a gas utility, as well as other key regulatory officials. The tour was organized by CALSTART in partnership with the Business Region Gothenburg.

Biomethane powers more than 8,000 transit buses, garbage trucks, and 10 different models of passenger cars in Sweden. The country has more than 25 biomethane production facilities and 65 filling stations.

Since biomethane is developed from methane sources that would normally release into the atmosphere it is considered one of the most climate-friendly fuels. Biomethane is 98% methane and easily meets the Swedish and California pipeline standards.

Biomethane is developed by heating up and breaking down biomaterials in a digester. Among the raw materials the Swedes feed their digesters are slaughterhouse waste, swine manure, and even grassy crops. The materials break down over a 20-day period and impurities are removed to produce the gas. In some cases, renewable biomethane is injected into Sweden’s natural gas pipeline network to augment supplies. The program is similar to the green energy program operated by some electric utilities in California.

Going forward, we will be working closely with Swedish and California government and industry officials to take concrete steps that help our biomethane industry grow. California is leading the nation in terms of using natural gas as a transportation fuel. We now want to enter the next phase where we expand upon that program and start utilizing biomethane.

—John Boesel, CALSTART President and CEO

CALSTART is a non-profit organization that works with the public and private sectors to develop advanced transportation technologies.



allen zheng

It looks like the Swedes will be on 100% biogas, more or less, by 2015. The question is how quickly can this be fully implmented for US biodegradable garbage? This would include the implementation of waste discrimination, like in many Japanese cities. Bins for degreadable waste (food waste, unrecyclable paper, biodegreable diapers, etc), recyclables, and non recyclables would have to be the norm. Then the waste biodegradable would be processed for methane, and compost. Most of the rest gets recycled, with a much smaller amount going to landfills vs today. This may solve some of the problems due to increasing garbage, and closing landfills.
___I can see places with poor soil that could use compost (and the organic carbon/minerals/nitrogen it provides). Austrailia, with hardly any mineral replenishing geological activity in the last 10 million years, can benefit greatly.
___On a sidebar, sewage treatment could do a similar process for methane, or another process to make algae for oil/biomass.

An Engineer

Let us play along. The anaerobic digestion technology described here, has the following characteristics:
1. Partial degradation: Only the biodegradable fraction gets degraded, and the conversion is not 100%.
2. Following from 1. there is a significant solid waste that must be disposed of. I know proponents would argue it serves as a soil "conditioner". Getting someone to accept it on their property is a different matter, though.
3. Following from 1. the overall efficiency must be low.
4. The process requires a 20 day retention time. That makes for some pretty large units, with associated inve$tment$.
5. The raw biogas is ~50% methane, ~50% CO2 and some other nasties (H2S, siloxanes, etc.). Getting it to 98% methane requires cleaning. Add to the inve$tment$ and subtract from the nett energy yield.
6. The product, biomethane, is a gas, with associated storage and transportation costs.

Sure, it is better than doing nothing (and letting all that GHG escape into the atmosphere).

An alternative would be Gasification-Fischer/Tropsch. The conversion would be much higher. Feedstock does not have to be biodegradable, anything that burns (paper, plastic, food waste, timber) will work. Even biohazards can be safely converted, thanks to process temperatures which would sterilize anything. Remaining solid waste would be ~100% inorganic and a much smaller quantity (i.e. easier to dispose of). Efficiency should be higher. Process units would be more complex, but much smaller. The liquid product can be blended at any ratio into existing fuel supplies and used in existing vehicles with no adjustment to engines.


Seems to me that you could run the waste product from the biomethane process through the gasifier / FT system so you could get the relatively easy to convert methane and the more expensive liquid fuels using the same feedstocks. All these technologies combined is the only solution that will work because we don't currently have systems that run on one single energy carrier.

An Engineer

OK, but what would be the point of having two plants in series, when one would do?

I don't get your point about the carrier, either. The existing fuel system run on a single carrier: liquid hydrocarbons. It has distinct benefits over alternatives. For the forseeable future, it would make sense to stick to that carrier.


The point of having two systems in series is that the first one is low-tech, very reliable, presumably efficient and allows the second system to help process a far larger total input.

A 20-day retention time isn't much compared to the lifespan of the landfill you'd be eliminating.

An Engineer

The point of having two systems in series is that the first one is low-tech, very reliable, presumably efficient and allows the second system to help process a far larger total input.
At the expense of producing less liquid fuel and more gaseous fuel. Unless you have a specific need for gas, why bother?

What makes the first system reliable? It is biological, so it is more temperamental. It is also not very efficient.

On top of that you introduce conflicting requirements: the first systems needs wet waste, the second needs dry waste. Nothing will kill overall efficiency like adding water for step #1 and then drying the feed for step #2.

Roger Pham

This is a very encouraging process: "Biomethane has been contributing to 45% of Sweden's methane, and the process is growing at 20% annually..." Hopefully, this will show other parts of the world how inefficient it is to ferment ethanol from corn kernel, the stuff that you can eat, while the biomethane in Sweden comes from biowaste.

At the same time, Northern Europe and California are also developing H2 for use as transportation fuel. I hope that they would put 2 and 2 together, to use hydrogen for local driving and commuting, while methane for long trips or when frequent fill-up with hydrogen would not be desirable, both in the same flexible-fuel vehicles capable of running on both H2 and methane.


Biogas is stupid, you will always get a lot more energy by simply burning the waste in a power plant and collect the electricity. But as always environmental politics is decided by what the general public belives is good. Biogas is almost like recycling and recycling is like the holy grail for some people.


Biogas is a by-product of treatment of organic slurries like sewage sludge or manure. These slurries could not be dewatered in any economucal way unless they undergo anaerobic digestion. Addition of some amount of plant biomass just improves the process by optimizing N/C ratio. As such anaerobic digestion is just the best way to treat these wastes. I agree that better quality organic stock could be used better way then for biogas production.

fyi CO2

The Swedes can't even clue Californians on blonde technologies



Sewage sludge can be dewatered and burnt in an economical way. I've seen it myself (and smellt it).


Something needs to replace the methane that heats all those homes in North America, that's why I think biomethane makes some sense, I don't think we need to start making all our cars to run on methane since there's only going to be so much of it available when the fossil sources are depleted. The residential and commercial natural gas network is already well established and just needs a sustainable source.



You are talking about already digested sludge! Primary (settled) and secondary (aerobic activated sludge) do not give up their water content! Only after anaerobic digestion amount of sludge is reduced five times and it can be dewatered on belt press and alike enough to be further thermally dried and burned (very polluting and nitrogen-fertilizer-wasteful practice, BTW)

Roger Pham

You have a good point. Biomethane eventually won't be sufficient to supply all of our household needs when fossil sources are depleted. That's why we will depend on solar or wind hydrogen to supplement our biomethane supply. Existing pipelines will need to be upgraded to carry H2 and methane mixture. Cars can run on H2 for local commute or short range, and for longer driving, fill it up with Hythane, which is a mixture of 20% H2 and 80% methane by volume. Most of the mileage will be for short-range daily commute where H2 will supply the bulk of our driving needs.


It makes more sense to use methane (or its precursors) as the storage element of an AE scheme and rely on electric propulsion for every-day use.  Hydrogen sounds nice, but the conversion losses and expense of high-efficiency converters like fuel cells make it far less useful than it looks.

I suspect that this is exactly why many people allied with the fossil-fuel industry are pushing hydrogen; it diverts mindshare and R&D from their real competition, which is Li-ion cells, zinc-air fuel cells and so forth.

Roger Pham

You haven't kept up with the latest in hydrogen development. We can expect one day that BEV and H2-ICE-electric hybrid will have the same solar to wheel energy efficiency. It will then be up to the battery manufacturers to come up with battery cheap enough and plentiful enough to power hundreds of millions of PHEV and capable of lasting for the life of the car. Still, a PHEV that can drive 50 miles for each charge will have a battery that can add several hundred pounds to the weight of the car, and thousands of dollars. In hot climate, battery life will shorten considerably, and in frigid climate, battery will not deliver sufficient charge nor power for driving.

In contrast, a ICE-electric hybrid designed to run on compresse biomethane with a 5000psi-tank for 360 miles can also be made to run on compressed hydrogen on the same tank at the same pressure for ~120 miles, WITHOUT the excess weight and WITHOUT the excess cost and WITHOUT THE EXTRA maintenance AND WITHOUT THE REPLACEMENT COST of a large battery pack sufficient for PHEV range of 50 miles. Processes are being developed to make hydrogen very efficiently and soon to be competitive with gasoline at current price.

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