The world's only carbon-negative power source (pictures)

BERKELEY, Calif. -- All Power Labs, a startup in this city across the Bay from San Francisco, makes what it says is the world's only carbon-negative power system.

Its PowerPallet systems come in 10- and 20-kilowatt configurations and produce a fuel using a process called gasification that will work in most engines by feeding in dense biomass. The company says that its system can produce power for about $1.50 per watt, and is being used in many developing nations to produce power for about a third of the cost of existing systems. Most buyers purchase the $27,000 20kW system.

In addition to producing carbon-neutral electricity, the machines also produce a carbon-rich charcoal that can be used as a very effective fertilizer. Because it pulls more carbon out of the sky than it puts back in, the company says the system is carbon-negative.

This chart, from All Power Labs, explains the major components of its machines.

This chart also explains the major components of the All Power Labs PowerPallet machines.

This is the machine's hopper, where users pour in the biomass, which can range from coconut shells to corn husks to wood chips. A full hopper can power three or four American households' power usage for three or four hours.

The benefit of using biomass is that it can be found in abundance and at low cost everywhere in the world where there are people.

This is the PowerPallet's reactor, known as a gasifier, which is used to process the biomass and generate clean fuel.

This is the machine's packed bed gas filter, which is made with washable foam elements.

This graphic explains, in very simple terms, how the PowerPallet works.

Tom Price, All Power Labs' director of strategic initiatives, shows several kinds of dense biomass that can be used to generate electricity with the PowerPallet. Among them are corn cobs, wood chips, coconut husks, and several others. The denser the material the better, the company says.

The PowerPallet converts about 20 percent of the biomass into a carbon-rich charcoal that is a very effective fertilizer.

Although All Power Labs only produces 10 kW and 20 kW machines, it recently got a grant from the US Department of Energy and the University of Minnesota to make a prototype 100 kW model.

Gasification is a power-generating process that has been around since the early 20th century. During World War II, a million vehicles were powered using fuel from gasification machines. Today, however, All Power Labs has developed a computer control system that it says makes the process far more efficient than any other manifestation of the technology.

In a small bit of humor, All Power Labs has printed a kitchen sink on its circuitry -- as in, it incorporates everything including the kitchen sink.

Early in All Power Labs' history, it installed a small version of its machine in the back of this Honda. They were able to drive the car back and forth across the Golden Gate Bridge a few times using just a couple of handfuls of walnut shells.

All Power Labs' original prototype is mounted on top of a shipping container at the company's Berkeley, Calif., headquarters.

The company also displays many iterations of its machines at its headquarters.

Tom Price, All Power Labs' director of strategic initiatives, shows off a proclamation from the city of Berkeley lauding the company for creating dozens of green-energy jobs. The company is proud of that honor, given that it was founded when a number of artists had to come up with a new way of generating power for their flamethrowers because Berkeley shut the electricity off at their compound.

This week, All Power Labs installed a PowerPallet outside San Francisco's Palace Hotel and used the machine to provide all the power for the Verge Conference, a green energy trade show.

Although Berkeley is one of the most expensive cities in the San Francisco Bay Area, All Power Labs is committed to making all its machines at its headquarters there. The company can turn out about one of its machines per day.