Fast Company has an article pitting large scale renewable power (and the associated transmission infrastructure) against small scale distributed generation - Why the Microgrid Could Be the Answer to Our Energy Crisis. This sort of comparison seems unhelpful - both options are better than coal or nuclear power, so why not compare the 2 new waves of the future against the relics of the past ?

In April 2007, a helicopter landed in a backyard in Johnson Valley, California, a desert hamlet of 440 residents on the outskirts of Joshua Tree National Park. "One of the neighbors went out and asked them what they were doing just a few hundred feet from his house," Jim Harvey, a local landowner, recalls. "They said, 'We're the Los Angeles Department of Water and Power, and congratulations! You're the lucky lottery winners of a brand new power line that's going to come right through the middle of your town.' "

That power line is called Green Path North -- an 85-mile-long high-voltage transmission wire from Los Angeles through public and private lands, connecting the city to potential geothermal and solar-thermal resources, with the whole shebang to be owned by the LADWP and paid for over the next decade by ratepayers. The cost: up to $1 billion just for the transmission line, plus untold billions for the not-yet-planned power plants themselves. Some 2,000 acres of desert would be sacrificed for a project that would, if it ever gets built, carry about 800 megawatts of renewable electricity -- enough for 600,000 homes.

Green Path North is pretty typical of the renewables push in the United States: big, expensive, slow, and spectacularly uncertain. Twenty-eight states have pledged to shift their energy mix to at least 10% renewables, and at press time, Congress was considering a national target of 15% by 2020. But if many of us see this moment as a defining one, a key opportunity to reassess how we create and use energy across the country, the federal government seems content to leave the owners of the old energy world in charge of designing the new one. Big utilities are pushing hard to do what they do best -- getting the government to subsidize construction of multi-billion-dollar, far-flung, supersize solar and wind farms covering millions of acres, all connected via outsize transmission lines. Nevada senator Harry Reid has introduced legislation to speed the way for a national "electric superhighway." (Former Vice President Al Gore is another champion.) "We need to have an efficient way to take energy created in often remote areas and move it to where it is needed," Reid said this spring on the Senate floor. "A cleaner, greener national transmission system -- an electric superhighway -- must be a top national priority."

But the men appear to be victims of a bad metaphor. There's nothing especially efficient or high tech about heavy-duty aluminum-steel cables; "line loss" -- the power lost during transmission -- runs as high as 10% on our overloaded grid. The power lines take years to propose, approve, and complete; Green Path North alone has gone through seven potential routes since 2006. And the LADWP is taking a flyer that the remote, large geothermal and solar power plants it's supposed to connect with will even be built. In all, the federal Bureau of Land Management has to date received almost 400 applications for large solar and wind plants covering 2.3 million rural acres. Only a few of those have undergone environmental assessments -- and that's only the first step in a multiyear planning, permitting, and building process. Meanwhile, utilities are making plenty of money off their existing investments in fossil-fuel power. It often seems that according to utilities, renewables are the power resource of the next decade, and always will be.

Harvey says he has a better idea. The founder of the Alliance for Responsible Energy Policy, he's no NIMBY complainer. "We're just the opposite; we want it in our backyard," he says. "We want to put solar panels on our roofs and our neighbors' roofs." The nearby city of Palm Desert rolled out a program last August funding fixed-rate loans to private homeowners for rooftop solar, and within weeks, the money had been spent and panels were up on roofs. "The choice is clear," says Harvey. "If you want renewables, you want 'em clean and you want 'em fast, and the best way to do that is [rooftops]. But the utilities have been so adamant about thwarting these programs. They are the ones that are standing in our way."

The evidence is growing that privately owned, consumer-driven, small-scale, geographically distributed renewables could deliver a 100% green-energy future faster and cheaper than big power projects alone. Companies like GE and IBM are talking in terms of up to half of American homes generating their own electricity, renewably, within a decade. But distributed power -- call it the "microgrid" -- poses an existential threat to the business model the utilities have happily depended on for more than a century. No wonder so many of them are fighting the microgrid every step of the way.

Theoretically, the microgrid is simple. Imagine you could go to Home Depot and pick out a wind or solar appliance that's as easy to install as a washer/dryer. It makes all the electricity your home needs and pays for itself in just a few years. Your home still connects to the existing wires and power plants, but it is a two-way connection: You're just as likely to be uploading power to the grid as downloading from it. Your power supply communicates with the rest of the system via a two-way digital smart meter, and you can view your energy use and generation in real time on your iPhone. Maybe you also have an electric car in the garage; the battery serves as backup storage for your house as well. And the best part: Assuming you produce more than you draw, instead of a monthly bill, you get a check.

A half-block from City Hall in Cambridge, Massachusetts, sits an unofficial prototype of this microgrid model. In 1983, when Sue Butler first bought her home, it was a condemned burned-out shell where police sent vagrants to crash. Today, the historic Italianate house built in 1858 has a comfortable artsy grace that matches the owner's; a cello and violin wait for a duet among a jungle of plants by the bay window. An elderly dog wheezes in the kitchen. On the roof, powering this cozy scene, sits a half-kilowatt microwind turbine and 5.5 kilowatts' worth of solar panels. The system was roughly half paid for by a $25,000 grant from the Massachusetts Technology Collaborative, which administers a fund collected from a surcharge on every electric bill in the state. The solar installation can produce two to three times as much energy as Butler's home needs, meaning she can run her meter backward and sell a surplus back to the grid, a procedure called "net metering."
Sue Butler's house can generate juice for two others. Put one on every block and soon you have a renewable-power plant.

A neat addition to Butler's system is the standard commercial meter that she finagled from NSTAR, the local utility. Unlike flat-rate residential electric meters, commercial meters show the price of power varying with usage over the course of the day. Butler can bank power in the batteries in her basement -- they hold enough to run her house for a week -- and sell it back to the grid at times of peak use. "It's a low-tech smart grid," says Jonah DeCola, the soft-spoken self-taught engineer and union carpenter who put together her system as proof of concept. DeCola is building a career cobbling together systems like this and teaching community college kids, new immigrants, and ex-cons the trade as well. He calculates the payback on Butler's $60,000 system at four-and-a-half years or less. "She's getting premium for her juice," he says.

The Guardian has an article on plans to expand micro-hydro generation in Britain - Canals and rivers to lead micro-hydropower revolution

Britain's canals and rivers have already been heralded as a low-carbon way to tranport Tesco groceries, a test-bed for hydrogen boats and a opportunity to build more wind turbines. Now they're being billed as a chance for micro hydropower to flourish under new plans unveiled today by British Waterways, which maintains 2,200 miles of the country's canals and rivers.

In partnership with The Small Hydro Company, British Waterways said it intended to build 25 small-scale hydro-electric schemes with a capacity of 40MW, enough to power 40,000 homes. While far smaller in capacity than offshore wind farms switched on in 2008, the hydro initiative hopes to raise £120m in private capital over the next three years, create 150 construction jobs and reduce CO2 emissions by 110,000 tonnes annually.

Underwater turbines will be installed next to existing weirs and will not affect the navigation of canals and rivers. Larger waterways such as the Trent and Severn rivers will be used for the first hydro power projects, with many of the installations likely to be located in the East Midlands and Yorkshire. It is hoped the first of the 25 hydro installations will be generating renewable electricity by 2010.

"Britain's waterways were the arteries of our economy, providing transport and power," said the environment secretary, Hilary Benn. "This scheme shows how with ingenuity and innovation they can once again deliver real economic, social, and environmental benefits, especially in tackling and adapting to climate change."

Last year British Waterways also announced plans to build wind turbines with 100MW of generating capacity, and more recently it said it wanted unused land by canals and rivers to be turned into allotments.

Technology Review has a look at efforts to introduce microbial fuel cells in Africa, on the basis they are easier to set up than small solar panels (probably the main source of power in off the grid Africa) - Microbes for Off-the-Grid Electricity.

Microbial fuel cells, which use electrodes in dirt to power a small motor, have long been more or less a laboratory curiosity. Because they generate such a small amount of power, developing them to charge devices would not be practical in places where electricity is readily available. However, Lebônê Solutions, a startup based in Cambridge, MA, aims to use microbial fuel cells to provide power to Africans who are off the grid. In some parts of Africa, a small amount of energy is enough for a few hours of lamp light in the evening, or for powering the ubiquitous cell phones--something that some residents will walk five hours to a generator to do, says Aviva Presser, a cofounder of Lebônê. The company is made up largely of Harvard University alumni and current Harvard students originally from African countries.

With funding from the Harvard Institute for Global Health, the team has recently completed a pilot study in Tanzania, where members brought six basic microbial fuel cells and taught residents how to use them. The team organized village meetings where team member and Tanzanian native Stephen Lwendo explained how to make the fuel cells.

The team found residents receptive to the idea of easy-to-grow power and keen to use the fuel cells to charge cell phones, run radios, and provide more light. "In Africa, people want to power [small] DC devices," as opposed to large AC devices like a refrigerator, says Lebônê cofounder Hugo Van Vuuren, a Harvard graduate and a South African native. The team hopes to develop the technology to make it competitive with other renewable energies in countries across Africa. Microbial fuel cells could have a distinct advantage because they are initially cheaper to build than a windmill and easier to set up than solar panels. What's more, they could last up to 10 years, says Lebônê cofounder David Sengeh.

Instead of using hydrogen as a fuel, as do conventional fuel cells, microbial fuel cells use naturally occurring microbes to generate power. Bacteria live in the anode, where they eat glucose, sewage, or other waste water, and turn that into electrons and protons. The bacteria transfer electrons to the circuit, which provides small amounts of power.

Inhabitat has a post on an interesting but possibly far-fetched concept to create "Nano vent-skin" materials that combine solar power generation, micro wind turbines and CO2 absorption capabilities into a fabric that could cover building surfaces.

There’s nothing like a towering wind turbine to inspire NIMBY sentiment from neighbors and city councils alike. Enter a striking new alternative energy concept by Mexican-born Agustin Otegui, who works with economies of a much smaller scale. He has conceived of a next-gen Nano Vent-Skin that sheathes structures in a shimmering solar weave studded with micro-turbines. The concept takes advantage of a structure’s maximum available surface space, and its modular composition allows it to retrofit our old buildings instead of pouring resources into new ones. Plus, the stunning superstructure incorporates micro-organisms to soak up C02.

In the past we’ve covered approaches to alternative energy that seek to synthesize solar with wind. It’s an exciting area to watch as technology improves and processes are streamlined, and Ostegui’s concept charts some innovative new territory.

The Nano Vent-Skin is a zero-emission material that takes a tri-partite approach towards energy efficiency. First, it soaks up sunlight via a photovoltaic layer, and transfers energy via nano-wires to storage units at the end of each panel. Second, its tiny turbines employ “polarized organisms” to create chemical reactions, generating power each time the turbine makes contact with the structure. Third, the organisms present in the inner skin of each turbine soak up C02.

At the core of the technology is an elaborate system of bio-engineered micro organisms which “have not been genetically altered; they work as a trained colony where each member has a specific task in this symbiotic process.” Ostegui even has plans for the system to be self-healing: “Every panel has a sensor on each corner with a material reservoir. When one of the turbines has a failure or breaks, a signal is sent through the nano-wires to the central system and building material (microorganisms) is sent through the central tube in order to regenerate this area with a self assembly process.”

Ostegui’s NVS may reside at the far end of future-forward thinking for now, but it presents some exciting concepts that may surface as science and technology work together to converge our existing energy systems.

The ABC's Catalyst show this week had a segment on green cement from a company called Zoobond - trying to reduce the huge carbon emissions that cement making currently entails.

An Australian company has started to make concrete which promises to dramatically cut the carbon dioxide ordinarily emitted during production. Concrete is the second most widely used material on earth, after water. Figures vary, but it’s estimated that the manufacture of cement, the reactive ingredient in concrete, is responsible for over 5% of the world’s CO2 emissions.

Using a technique to make geo-polymers similar to those found in some natural volcanic rocks, a concrete alternative called E-Crete is now being manufactured in Melbourne, which claims to have reduced the amount of CO2 ordinarily emitted in the manufacture process by an estimated 80-90%.

Narration: What’s the fast growing source of greenhouse gas?

You might be surprised but it’s cement. Cement’s already the 3rd largest man-made source of carbon dioxide - more than two billion tonnes of it a year. That’s after fossil fuels and defrorestation. And because of all the construction going on around the world, cement’s carbon footprint is growing rapidly.

In May 2007, the Mayor of London laid down a gauntlet: 60% cuts in carbon emissions by 2025 – that’s 25 years ahead of the UK’s national target – 25 years ahead of anywhere else in the world. So can a city do what a nation can’t?

London has faced many challenges in its long and colourful history, but this could be its biggest. Like all great cities, it has an insatiable hunger for power. 75% of the worlds’ carbon emissions come from cities. And yet cities are some of the places most at risk from climate change.

Stopping the City drowning is an unenviable responsibility, but it has fallen on the shoulders of Allan Jones MBE because of the extraordinary thing he did in the English town of Woking. Once there, he set the town on the path to independence of the national electricity grid, by generating all its own power.

Now, Allan has been asked to repeat what he did for Woking in Greater London - a city 75 times the size. London has a proud history of transformation under duress, but like the barriers on the Thames itself, the barriers that Allan and his compatriots face are immense. ...

Combined heat and power is not new – Manhattan was set up with it in the 1880’s. But when modern, centralised power stations were invented, CHP was quietly abandoned – Manhattan’s surrounds are on the grid.

In energy terms, though, centralised power stations are far less efficient. 2/3 of the energy produced is thrown away into the atmosphere as heat – with further losses over the grid.