Green Tech

Municipal trash giant Waste Management on Thursday created a joint venture that will turn waste into energy using technology that it says is cleaner than incinerators.

S4 Energy Solutions is a joint venture which will use plasma gasification technology from InEnTec of Bend, Ore., to build distributed energy systems. Waste Management financed the creation of the venture, marking the first time that the trash collector has invested in gasification technology, said Senior Vice President Joseph Vaillancourt.

The new company plans to build distributed energy systems that use separated industrial waste as a "feedstock." For example, the company plans to design systems that can turn medical waste into electricity at hospitals, said Jeffrey Surma, the president and CEO of S4 Energy Solutions.

There are a number of mostly small companies that are developing trash-to-energy systems around gasification. One company, Enerkem, on Wednesday passed the environmental regulatory process and won approval to build a facility to turn municipal solid trash into ethanol and chemicals in Edmonton, Alberta.

Rather than burn trash, gasification heats the material at very high temperatures until it breaks down and produces a synthesis gas, or syngas. That syngas can be burned in a natural gas turbine, which is considered a relatively clean way to make electricity. S4 Energy Solutions said that it can also make ethanol, other liquid fuels, or potentially hydrogen.

The InEnTec product has a process for cleaning the syngas. Initial tests show that the level of environmental pollutants dioxins and furens released is low, Surma said.

(Credit: InEnTech)

"The emissions from a power generating facility would be far better than EPA requirements, comparable if not better than a power generator operating on natural gas," he said, adding that the company hopes to have customers later this year.

The technology was originally developed in the early 1990s at the Pacific Northwest National Laboratory and the Massachusetts Institute of Technology, Surma said.

S4 Energy's planned gasification systems won't replace incinerators but they do provide an option for on-site energy generation. Waste Management will provide ancillary equipment, such as sorting, to create a full waste-to-energy system, Vaillancourt said.

Earth Day, which will be celebrated on Wednesday, is a good time to look at the way electronics are using and wasting energy.

Among the culprits are devices that suck power while not in use. I'm not sure how they arrived at this figure, but the U.S. Department of Energy estimates that "in the average home, 75 percent of the electricity used to power home electronics is consumed while the products are turned off." The government advises unplugging devices or using a power strip to turn them off, but this is sometimes inconvenient as it will disable remote controls and, in some cases, require the device go through a time-consuming start-up.

Some devices are designed to run 24 hours a day. Digital video recorders, for example, are always standing by to record your programs. About 18 months ago, I put an energy meter on some of the devices in my home and discovered that my TiVo was using 30 watts 24/7 and a Motorola Comcast PVR I was using at the time was sucking 40 watts regardless of whether it was recording a program.

Little power bricks also consume electricity even when nothing is connected to them, so it's a good idea to unplug items like cell phone chargers and iPod chargers when not in use.

Many people leave their personal computers on 24 hours a day. If the machine successfully goes into sleep mode, the power drain is relatively low. But it's not uncommon, especially for Windows systems, for the machine to run at full-throttle when it should be sleeping.

If you do leave your machine turned on--even while at lunch--try to configure it to go into sleep or "stand by" mode after say 15 or 20 minutes of inactivity. In theory, it will wake up as soon as you touch the keyboard or move the mouse. Unfortunately, Windows sleep mode doesn't always work properly. Sometimes it fails to go into standby. And if it does fall asleep, it sometimes fails to wake up properly. There are a variety of reasons for this, including some software that demands full power. But often the culprit is one or more device drivers or USB devices that either fails to let the machine sleep or interferes with its ability to wake up.

Screen saver software does not save energy. It's much better to turn off your monitor when you take a break. CO2 Saver, a free program for Windows XP and Vista, can help you manage your PC's sleep behavior.

In my limited experience as a beta tester, Windows 7 seems to do a better job at sleeping and waking than Vista or Windows XP, but this is machine- and software- dependent. So until we see widespread deployment, we won't know if Microsoft has solved the problem. Mac OS X seems to be less prone to insomnia or failing to wake up, but it's not exempt from these problems.

PCs with ultra-fast processors and display adapters tend to use more power than somewhat slower systems. In general, notebook PCs are considerably more energy efficient than desktops, partially because they're designed to run on batteries and also because they have built-in screens that are powered from the same power supply as the rest of the machine. All-in-one desktops are generally more eco-friendly than machines with an external monitor.

Even though it doesn't affect your own power meter, the electrical demands of Internet services also add up. Every time you do something online, a server somewhere might have to access a hard drive while routers throughout the Internet are using energy to transmit the data that you're sending and receiving. I'm not suggesting you cut back on Internet use--just be aware that it's not carbon free.

And speaking of carbon, a McAfee-commissioned report issued last week by ICF International found that 62 trillion pieces of spam sent in 2008 had the same environmental impact as 3.1 million passenger cars or 2.4 million U.S. homes. A single piece of junk e-mail adds 0.3 grams of carbon dioxide, which is like driving three feet.

The ICF report estimates that e-mail from the average business user accounts for 288 pounds of carbon dioxide per year, with 22 percent of that usage related to spam. More than half the energy wasted by spam results from users viewing and deleting it, according to the report.

The process of getting spam from one place to another involves multiple phases--all of which consume energy. First, there is the scraping of Web sites to harvest e-mail addresses, followed by code and copy writing to initiate the spam campaign. Next comes sending the messages via the Internet to an army of infected "zombie PCs," all of which use energy to receive and retransmit the messages. Then there is the impact on servers that store and send the spam, the routers and other Internet infrastructure, and, of course, the PCs that finally receive and display the junk mail.

Add to that the resources used to attempt to filter the spam and it's easy to understand the potential environmental impact. If every in-box had spam filters, according to the report, we could cut energy waste by 75 percent. But eliminating spam at the source would save even more.

Rather than stay in the ground, trash from the Three Rivers Landfill in Ponotoc, Miss., will be turned into ethanol.

Montreal-based Enerkem on Thursday announced plans to produce 20 million gallons a year of ethanol from waste at the Mississippi landfill in a project valued at $250 million.

This is some of the equipment used in Enerkem's multistage process for convering waste to fuel.

(Credit: Enerkem)

The "feedstock" for the ethanol will be municipal solid waste, as well as wood residues from forest and agricultural activities, according to Enerkem.

The company's process can sort household trash, diverting material that can be recycled and processing the rest into ethanol, a liquid fuel blended with gasoline.

The project is one of only a few in North America to convert waste products into ethanol or electricity using processes that waste-to-energy companies say is cleaner than existing technologies such as incineration.

After sorting and drying the waste, Enerkem breaks down the material with heat and pressure using a gasifier. The gasifier creates a synthesis gas that is a mix of carbon monoxide and hydrogen. That synthesis gas, or syngas, is then converted into ethanol or other chemicals.

The company, which was founded in 2000, has built a few demonstration facilities in Canada using both municipal solid trash and utility poles as a feedstock. At a conference earlier this month, company CEO Vincent Chornet said the technology is largely developed and that Enerkem is now looking to commercialize the process more broadly.

Coskata and BlueFire Ethanol are two other cellulosic-ethanol companies that plan to turn both wood chips and municipal solid waste into ethanol.

BOSTON--To many communities, trash-to-energy means burning garbage. But a handful of companies say they are close to bringing cleaner technology to market for making electricity or ethanol from waste.

At a panel discussion on waste-to-energy at the AlwaysOn GoingGreen East conference here on Tuesday, representatives from four companies detailed their plans to use gasification to convert waste products to usable energy. Some products are ready to be deployed more widely while others are still in the pilot testing phase.

The promise of using municipal solid trash or other waste products for useful energy is tantalizing: it's a renewable resource and reduces the need for methane-emitting landfills or incineration.

But making the technology less expensive, along with resistance from communities over environmental concerns, remain formidable barriers.

"It's a bit of minefield. We all run companies where 40 companies have failed before us," said Bill Davis, the CEO of Ze-Gen, a start-up which has a pilot facility for turning construction debris into electricity.

Workers at Ze-Gen's waste-to-electricity test facility in Bedford, Mass, where construction debris is heated in an oxygen-starved chamber to break the material down into its component elements, including hydrogen and carbon monoxide.

(Credit: Ze-Gen)

Representatives from the four companies--Ze-Gen, IST Energy, Enerkem, and Plasco Energy Group--took pains to point out that gasification is different and cleaner than combustion.

In a gasifier, a feedstock like municipal trash is heated at high temperatures and pressure, which breaks down the material into a synthesis gas, which contains hydrogen and carbon monoxide. That synthesis gas, or syngas, can be burned in a commercial turbine to make electricity or heat.

Plasco Energy Group appeared to be furthest along in terms of commercializing the technology. It has a facility in Ottawa, Canada, that handles 100 tons a day of municipal garbage left over after recyclable items have been removed. The company plans to open a manufacturing facility this summer to produce more of these 100-ton modules and is in discussion with communities in California, British Columbia, France and the U.K., according to CEO Rod Bryden.

Bryden hopes to replicate the model in Ottawa where the waste-to-energy facility is sited in the city and the community holds the company to high environmental standards for air quality and waste water disposal.

After creating a syngas, its equipment can separate residual materials and turn them into products, so that 99 percent of the input is used. Left-over solids, for example, can be mixed to make asphalt or other construction equipment, Bryden said.

"One of the things about garbage (as a feedstock) is that it's where the people are and that's where the energy is used," he said. Wind and solar, by contrast need to have transmissions constructed. "The first barrier to overcome is environmental (such as air quality). If you can't get by that, you won't be able to get into business."

Costs, too
Enerkem uses a gasification process as well, but makes ethanol rather than electricity. Last year it signed a contract with Edmonton in Canada to use municipal trash which will be converted into ethanol. It also has a demonstration plant in Westbury, Canada to use utility poles as a feedstock.

It plans to open a facility in Montreal, which took only four months to be permitted. By contrast, the last incinerator in the U.S. was built in 1996, according to Vincent Chornet, the CEO of Enerkem.

Next week, the company will announce plans for another waste-to-ethanol facility in Mississippi, he said.

Permitting, however, remains a formidable barrier, said Stu Haber, the CEO of IST Energy, which has developed a waste-treatment machine that can fit onto a flatbed truck. It's aimed at hospitals, prisons, and other buildings that generate at least two tons of trash a day.

Regulations for waste-to-energy were not written for gasification technology, which means that state agencies don't know how to deal with IST Energy's product, which the company intends to start manufacturing this summer.

"If we can't (get through) restrictions in government agencies, we'll have to go out business and it will make it harder for the industry," Haber said.

Also, within communities there's opposition from people who associate waste-to-energy with incineration, noted Ze-Gen's Davis.

On a technical level, making sure that a gasification can produce enough energy to be a replacement for fossil fuels, such as natural gas, still remains a challenge. Ze-Gen's business model, for example, is to get a high-quality fuel that can replace natural gas at a power plant facility. But with falling fossil fuel prices, the target is harder.

"Our competitor effectively is landfill most of the time so the biggest long-term issue is economics," said Ze-Gen's Davis.

Updated 9:45 a.m. PT with clarification on Enerkem's different facilities.

When a school or office building thinks about distributed energy, it usually means solar panels propped up on a roof.

A small company called IST Energy has another vision: it's developed a shipping container-size contraption that turns your building's trash into electricity and heat. The company is expected to unveil the unit, called the Green Energy Machine (GEM), on Monday.

The idea behind the GEM is to offset a building's energy use while dramatically cutting trash disposal fees. The cost of trash removal can vary greatly, but a university or office park with a number of buildings could pay about $200,000 a year, according to IST Energy executives.

The company says the GEM is clean technology because it doesn't burn the trash. Instead, the machine uses gasification, a process that overall pollutes less than combustion. A number of clean-tech companies are trying to combine gasification with renewable sources of fuel, namely municipal solid waste or biomass.

A demonstration unit of the Green Energy Machine from IST Energy that converts trash into energy.

(Credit: Martin LaMonica/CNET Networks)

The GEM unit is designed to take up as much space as three parking spaces, making it suitable for office buildings, hospitals, and the like. Metal and glass have no energy content, so they should be recycled. But everything else--food, cardboard, plastics, agricultural wastes--can go in.

"Normally, when we tell people what we're doing, they say, 'You can do that? I had no idea that was possible," said Stu Haber, president and chief executive of IST, which is based in Waltham, Mass.

The company, which was spun out of a research and development firm, says it can convert 95 percent of the waste--up to three tons of trash a day--into usable energy. The remaining 5 percent is ash. With three tons of trash a day, a unit can provide enough electricity and heat for a 200,000 square-foot building holding about 500 people, it says.

So far, a handful of universities, a municipality, and a real-estate developer have come by its Waltham, Mass. offices for demonstrations.

Got a big trash bill?
Haber said the unit pays for itself relatively quickly but realizes that the novelty of the GEM could make it a tough sell. He hopes to sell between 5 and 10 units this year. "The first GEM will be the hardest one to sell," he said. Noise from the machine could also be a barrier.

Corporate purchases of solar panels have been growing rapidly, depending on a state's incentives. Haber argued that many companies invest in solar energy to reduce their carbon footprint in a visible way, but a purchase of a GEM can be driven entirely by money, he argued.

Loading garbage into the demonstration unit of the Green Energy Machine.

(Credit: Martin LaMonica/CNET Networks)

Feeding the maximum of three tons of trash will yield about 120 kilowatts of electricity and about double that in heat, which will fulfill about 15 percent of a building's energy needs, IST Energy figures. The bigger financial benefit is in cutting disposal fees, Haber said.

With an up-front cost of $850,000, a GEM unit will have a payback in three to four years, the company calculates. More likely, those interested will go with a leasing option that would eliminate the hefty up-front investment.

"Everybody loves the fact that they're helping the environment, but because we're talking to businesspeople, I have to assume that they're interested because of the very quick payback," he said.

There's also a 10 percent federal tax credit available for this sort of renewable energy, Haber said.

Squeezing more value from refuse
From the end user's point of view, the GEM is designed to be simple. Through a loader, trash goes into the machine, which shreds the garbage.

Then the machine removes moisture and creates pellets--shaped just like the sawdust pellets used in pellet stoves. Then the pellets are put into an air-fed gasifier designed by the company, which generates what is called a synthetic gas, or producer gas, which typically contains mostly hydrogen and carbon monoxide.

The dark pellets were made from office trash. On the right are sawdust pellets used in pellet stoves.

(Credit: Martin LaMonica/CNET Networks)

That gas is the fuel for making electricity or heat. IST Energy recommends that the best energy source would be a natural-gas microturbine, which would need to have its setting adjusted, or a generator. It takes about two hours before the GEM runs from its own energy output, so the main carbon emissions come from burning the synthetic gas.

Garbage is already used as fuel source in a number of places. Some landfill operators capture methane from degrading trash to make electricity. Trash incinerators, too, can create some usable energy, but they are considered inefficient and polluting.

Looking to reduce shipments of diesel fuel, the U.S. Army last year tested portable trash-powered generators in Iraq, but the project is said to have not met all its goals.

For energy technology firms looking for a cheap source of fuel, trash appears to be attracting more interest.

Another Boston-area company called Ze-Gen is pursuing the same general idea as IST Energy. Last week, it raised a Series B round of $20 million to build a facility to take construction debris and make electricity at a central location using a gasification process.

Another firm, InEnTech in Oregon, is pursuing a different technology process to get the most energy out of household garbage.

Many of these firms have yet to test their products at commercial scale. But at a time when people are seeking clean and renewable-energy sources, waste may come full circle and become a valuable commodity again.

Updated at 3:00 p.m. PT to correct reference to synthetic gas.

Waste-to-energy firm Ze-Gen said Tuesday that it has raised money to further develop and commercialize its technology for converting municipal solid waste to electricity.

The company announced a series B round of $20 million that was led by a division of the Oman-based conglomerate Omar Zawawi Establishment.

Workers at Ze-Gen's waste-to-electricty test facility in Bedford, Mass.

(Credit: Ze-Gen)

There are a handful of firms developing different processes for converting municipal solid waste into usable energy. There are landfills that capture methane gas, which can be burned for electricity. Energy from incinerated trash can be used, too, but it is considered inefficient and polluting.

Ze-Gen uses presorted construction debris, which is put through a gasification process, where the trash is heated and put under pressure. Unlike burning, gasification yields what's called synthetic gas, which can be burned to make electricity.

The company has a demonstration facility in Bedford, Mass., where it intends to supply electricity to the local utility.

Last year, the original developers of the core technology filed suit against Ze-Gen, alleging that the intellectual property was misappropriated. Company executives have said the case has no merit.

Saving on fuel isn't a question of conservation for the military. It's about saving lives.

The U.S. Army is testing two prototype generators in Iraq that run on garbage, rather than diesel fuel.

The Tactical Garbage to Energy Refinery (TGER, pronounced "tiger"), was co-developed with Purdue University and deployed in May at Victory Base camp in Baghdad, where it will be tested until August.

A waste-to-energy generator being tested by the U.S. military in Iraq.

(Credit: U.S. Army)

The purpose of the unit is to cut down on the amount of diesel fuel used and to cut down on the amount of garbage that camps generate, which are both security risks.

"Those convoys that carry fuel are also known as targets," said James Valdes, scientific adviser for biotechnology at the U.S. Army Research, Development & Engineering Command. "Officers say 'We don't calculate the cost of fuel in dollars, we calculate it in blood.'"

Handling garbage is a logistical challenge, too, because the Army hires contractors who need to be followed.

Right now, the Army's trash goes up in smoke by burning it. The problem with incinerators, though, is that they require a lot of energy to run and many people to operate it.

TGER uses a variety of technologies to fuel a standard 60-kilowatt electrical generator.

People put trash into a chute and then the wet waste--like food slop--is separated from the rest. The cardboard, plastic, and other dry trash are crushed and pelletized.

Those pellets are then put into a gasifier, which heats them until they turn into synthetic gas--fuel for the generator.

Developers found that the relatively low-grade fuel from the trash over-heated the generators and maxed output at about 40 kilowatts.

So it created a system to convert the sugar-rich wet wastes (apparently, U.S. soldiers drink a good amount of Kool-Aid) into a form of ethanol. The wet waste is treated with enzymes and then fermented into hydrous ethanol--a mix of 85 percent pure ethanol and water, Valdes explained.

That ethanol is blended in with the synthetic gas, which boosts the generator's output to 55 kilowatts.

Starting up the contraption takes 6 hours and still requires 5 percent of the diesel the generator usually uses, or about 1 gallon per hour.

Compared to an incinerator, TGER is far more efficient at converting garbage to usable energy, said Valdes, who also said it runs at 90 percent efficiency. And it significantly cuts down on the amount of garbage that needs to be trucked around.

"Ultimately, what we would like to do is have a clean-sheet design so that you could automate it more. So you literally put trash in one end and electricity comes out the other," Valdes said.

If the TGER units work well in the harsh Baghdad conditions, he envisions the generator will be deployed in smaller camps, where the higher percentage of food waste can improve efficiency.

Valdes said the portable generator could also be used in disaster-relief situations where there is a lot of trash and the need for generators. The U.S. Navy has shown interest in the unit as well.

Trash, as it turns out, is an attractive feedstock. There are several commercial companies developing technologies that use wastes as fuel.

Cellulosic ethanol companies convert agricultural or forestry residues into ethanol, while portable generators use similar feedstock, such as wood chips, to make electricity.

A number of companies are also trying to convert municipal solid waste into ethanol using a range of processes.

EnerTech Environmental has attracted $42 million to build out facilities that turn human and industrial wastes into fuel.

The funding, announced on Monday, was co-led by Citi's Sustainable Development Investments (SDI) unit and Masdar Clean Tech Fund, which is financed in part by the Abu Dhabi Future Energy Company.

A Rialto, California waste-to-energy plant in construction with waste storage towers in background.

(Credit: Enertech Environmental)

EnerTech Environmental's technology takes high-moisture biosolids, including sewage sludge or agricultural wastes, and treats it with heat and pressure to separate water from it.

What comes out the other end of its SlurryCarb process is water that is sent back to wastewater treatment plants and a solid which it calls E-Fuel.

That solid can be burned in facilities that already use coal with little or no change, according to a company representative.

The company's first plant is in Rialto, Calif., where the waste fuel is being burned at the cement kiln. The ash from the combustion is even incorporated into the cement.

On the whole, the process consumes less energy than the fuel itself contains, according to the company. In the future, it's conceivable that EnerTech Environmental's plants could run on its own fuel.

The second round of funding will be used for construction of different plants. The Rialto facility is supposed be operating by the end of this year.

Its target market are municipalities. Many human waste facilities are facing more stringent environmental regulations and are having trouble finding more space for landfill, EnerTech's representative said.

The company is not the first looking to convert waste of various forms into usable energy.

There are a number of companies looking to convert agricultural and animal wastes into transportation fuels.

Another company, called Ze-Gen, has developed a process for treating municipal solid waste or construction debris to turn into a synthetic gas that can be burned to make electricity.