Tawanai

Via TelecomPk.net

In 2008 I wrote about VNL and its efforts to create low power base stations. Here’s an update about their work which appeared at Technology Review.

An Indian telecom company is deploying simple cell phone base stations that need as little as 50 watts of solar-provided power. It will soon announce plans to sell the equipment in Africa, expanding cell phone access to new ranks of rural villagers who live far from electricity supplies.

Over the past year, VNL, based in Haryana, India, has reengineered the traditional technology of the dominant cellular standard, called GSM, in order to create base stations that only require between 50 and 150 watts of power, supplied by a solar-charged battery. The components can be assembled and booted up by two people and mounted on a rooftop in six hours.

One such station–dubbed a “village station”–can handle hundreds of users. Groups of such village stations feed signals to a required larger VNL base station within five kilometers. In turn that larger station, which is also solar-powered, relays signals to the main network. The village station can turn a profit even if customers spend on average only $2 a month on the service, instead of the $6 required to make traditional systems cost-effective, the company says.

“We’ve scaled down the cost, the energy, and the equipment so that almost anybody can deploy it,” says Rajiv Mehrotra, VNL’s CEO. “It lends itself to many business models that can serve the bottom of the pyramid,” a reference to the roughly 1.5 billion rural people who do not have access to electricity grids around the world.

To date, some 50 VNL base stations have been installed in the Indian state of Rajasthan, introducing thousands of people to cell phone service for the first time. An African rollout is imminent, the company says, without elaborating. The initial batch of 50 stations support voice and data transmission–but not initially text-messaging, a decision mainly based on the fact that many new users may not be able to read or write.

Besides enabling basic communication, cell phones can provide enormous financial opportunities for rural people, especially if those people adopt services that provide banking and lending via cell phone. More than half of India’s 1.1 billion people lack any access to basic financial services, and instead pay usurious rates to local loan sharks. Furthermore, while microlending can lift people from poverty, only about 150 million people worldwide use such services. Expanded cell networks, together with banking programs geared to the rural poor, could change all of that.

Clean Technology, Consumers, Innovation

As part of our new technology series, this post looks at use of nano particles to improve solar energy performance. This report comes via Technology Review.

Inexpensive thin-film solar cells aren’t as efficient as conventional solar cells, but a new coating that incorporates nanoscale metallic particles could help close the gap. Broadband Solar, a startup spun out of Stanford University late last year, is developing coatings that increase the amount of light these solar cells absorb.

Solar antenna: The square at the center is an array of test solar cells being used to evaluate a coating that contains metallic nanoantennas tuned to the solar spectrum. Credit: Brongersma lab, Stanford

Based on computer models and initial experiments, an amorphous silicon cell could jump from converting about 8 percent of the energy in light into electricity to converting around 12 percent. That would make such cells competitive with the leading thin-film solar cells produced today, such as those made by First Solar, headquartered in Tempe, AZ, says Cyrus Wadia, codirector of the Cleantech to Market Program in the Haas School of Business at the University of California, Berkeley. Amorphous silicon has the advantage of being much more abundant than the materials used by First Solar. The coatings could also be applied to other types of thin-film solar cells, including First Solar’s, to increase their efficiency.

Broadband believes its coatings won’t increase the cost of these solar cells because they perform the same function as the transparent conductors used on all thin-film cells and could be deposited using the same equipment.

Broadband’s nanoscale metallic particles take incoming light and redirect it along the plane of the solar cell, says Mark Brongersma, professor of materials science and engineering at Stanford and scientific advisor to the company. As a result, each photon takes a longer path through the material, increasing its chances of dislodging an electron before it can reflect back out of the cell. The nanoparticles also increase light absorption by creating strong local electric fields.

Energy, Innovation, Solar, research

Since 2002, venture-capital investments in cleantech world-wide have soared from about $1 billion to an estimated $5 billion to $6 billion this year, according to the Cleantech Group, a San Francisco market-research firm. After experiencing one of its first back-to-back quarterly declines in March, venture funding for cleantech, much of it based in California’s Silicon Valley, has resumed its climb.

In the U.S., the lack of a strong Copenhagen deal may set back some of these investments, already hurt by falling oil prices. But the Obama administration still plans to use the Environmental Protection Agency to clamp down on the nation’s greenhouse-gas emissions, and the Energy Department remains committed to spending billions in public funds to jump-start alternative-energy technology. In the European Union, companies still have to comply with laws that require member nations to reduce emissions collectively to 20% below their 1990 levels by 2020, despite the summit’s lack of binding targets.

More from WSJ:

On a smaller scale, California is pursuing a program to garner a third of its electricity from renewable sources by 2020, more than double current levels. Most Northeastern states are expected to cut carbon-dioxide emissions, based on regional targets.

The adoption of renewable-energy standards, completed or under way in many states, should boost demand for technologies that make electrical grids more efficient, says Dan Adler, president of the nonprofit California Clean Energy Fund, set up by the state to help spur cleantech investment. Such efforts have fueled the growth of Silver Spring Networks Inc., a Redwood City, Calif., grid-technology provider, which has tripled its work force since 2008 to about 450.

“From our standpoint, we have been cheerleading Copenhagen,” says Eric Dresselhuys, the company’s executive vice president, “but it’s not a direct impact on this business.”

Many U.S. states will continue to shift toward lower-carbon fuels, says Michael Peevey, president of the California Public Utilities Commission, which regulates investor-owned electric, gas and water utilities in the state. California is “not going to turn back,” he says.

Officials at Iberdrola, the Spanish power company and the world’s biggest renewable-energy company say they are evaluating investments based on local policies, such as renewable-energy standards in states like Texas.

Some businesses, worried about a patchwork of federal and state regulation, are still pushing for Congress to enact a nationwide system for cutting carbon-dioxide emissions. But the prospects for congressional action in the 2010 election year look dim.

China, spurred in part by its desire to reduce dependence on foreign oil, remains committed to a sweeping energy efficiency program that calls for cutting carbon intensity, a measure of emissions relative to the size of the economy, by 40% to 45% from 2005 levels by 2020. That means government support for alternative energies, and for Chinese companies in that field, is likely to continue to grow.

Gao Jifan, chief executive of Trina Solar Ltd., a Chinese maker of solar panels, says the continuous cost reductions being achieved by solar-panel producers are making the technology more affordable. “So the outlook for its development is unstoppable,” he said in a statement.

Clean Technology, Energy, Innovation, Renewable Energy

Electrifying vehicles could slash petroleum use and help clean the air (if electric power shifts to low-carbon fuels like wind or nuclear). But it’s going to take better batteries.

In a lithium-air battery, oxygen flows through a porous carbon cathode and combines with lithium ions from a lithium-metal anode in the presence of an electrolyte, producing an electric charge. The reaction is aided by a catalyst, such as manganese oxide, to improve capacity.

Lithium-ion batteries, common in laptops, are favored for next-generation plug-in hybrids and electric vehicles. They’re more powerful than other auto batteries, but they’re expensive and still don’t go far on a charge; the Chevy Volt, a plug-in hybrid coming next year, can run about 40 miles on batteries alone. Ideally, electric cars will get closer to 400 miles on a charge. While improvements are possible, lithium-ion’s potential is limited.

One alternative, lithium-air, promises 10 times the performance of lithium-ion batteries and could deliver about the same amount of energy, pound for pound, as gasoline. A lithium-air battery pulls oxygen from the air for its charge, so the device can be smaller and more lightweight. A handful of labs are working on the technology, but scientists think that without a breakthrough they could be a decade away from commercialization.

Via: WSJ, Diagram Source: EDSRC.

Cars, Innovation battery, car

A Swiss company says it has developed rechargeable zinc-air batteries that can store three times the energy of lithium ion batteries, by volume, while costing only half as much. ReVolt, of Staefa, Switzerland, plans to sell small “button cell” batteries for hearing aids starting next year and to incorporate its technology into ever larger batteries, introducing cell-phone and electric bicycle batteries in the next few years. It is also starting to develop large-format batteries for electric vehicles.

This graphic illustrates the multilayered structure of a ReVolt rechargeable zinc-air battery. From top to bottom: the battery cover, which lets in air; a porous air electrode; the interface between electrodes; the zinc electrode; the casing. Credit: ReVolt

The battery design is based on technology developed at SINTEF, a research institute in Trondheim, Norway. ReVolt was founded to bring it to market and so far has raised 24 million euros in investment. James McDougall, the company’s CEO, says that the technology overcomes the main problem with zinc-air rechargeable batteries–that they typically stop working after relatively few charges. If the technology can be scaled up, zinc-air batteries could make electric vehicles more practical by lowering their costs and increasing their range.

Unlike conventional batteries, which contain all the reactants needed to generate electricity, zinc-air batteries rely on oxygen from the atmosphere to generate current. In the late 1980s they were considered one of the most promising battery technologies because of their high theoretical energy-storage capacity, says Gary Henriksen, manager of the electrochemical energy storage department at Argonne National Laboratory in Illinois. The battery chemistry is also relatively safe because it doesn’t require volatile materials, so zinc-air batteries are not prone to catching fire like lithium-ion batteries.

Via Technology Review

Electronics, Energy, Innovation, research batteries, volt

Fool’s gold, also called pyrite or iron sulfide, can be unearthed just about anywhere, from the hills of California to the villages of Yunnan Province in China. But instead of digging pyrite up, researcher Cyrus Wadia is making pure nano particles of the compound from iron and sulfur salts in his lab at the University of California, Berkeley. His ultimate goal is to turn fool’s gold into real treasure: an inexpensive solar cell.

Today, most solar cells are made of silicon, but they are expensive: though silicon is abundant, turning it into photovoltaics requires extensive, energy-intensive processing. Materials such as cadmium telluride and copper indium gallium diselenide are simpler to process, yielding thin-film cells that cost less to produce. But the elements needed to make these compounds, such as tellurium and gallium, are too rare to meet global energy demands.

So Wadia did a study of possible solar-cell materials, examining not only their chemistry and physics but also their availability. One of the standouts was fool’s gold: it is abundant and cheap, and it has optical properties that allow it to efficiently convert sunlight into electricity. “The theoretical efficiency of iron sulfide is 31 percent. That’s as good as silicon,” says Wadia. What’s more, 20 nanometers of pyrite can absorb as much light as 300 micro meters of silicon. Because it absorbs so much more light, it can be made into thinner cells, which require less raw material.

Via Technology Review

Clean Technology, Energy, Environment, Innovation, Solar

Clean Technology, Energy, Innovation, Solar, Wind

Could this new technology lead the way to a new and cleaner coal? Here’s Technology Review’s article about this.

The industrial boomtown of Dongguan in southeast China’s Pearl River Delta could soon host one of the country’s most sophisticated power plants, one that uses an unconventional coal-gasification technology to make the dirtiest coal behave like clean-burning natural gas. Its developers, Atlanta-based utility Southern Company and Houston-based engineering firmKBR, announced the licensing deal with Dongguan Power and Chemical Company this month.

Dongguan Power plans to implement the gasification scheme at an existing 120-megawatt natural-gas-fired power plant, turning it into an integrated gasification combined cycle (IGCC) plant that uses cheap, moisture-laden lignite coal. The retrofit should be operating in 2011. That will provide its developers with a demonstration to determine whether technology will work in larger IGCC plants and whether it is a process suitable to integrate carbon capture and storage technology, according to John Thompson, director of the Coal Transition Program for the Clean Air Task Force, a nonprofit environmental consulting firm based in Boston. “They want to show that this works,” says Thompson.

Southern and KBR’s gasification design can use dirty coal because, compared to other gasification reactors, it uses a relatively slow, low-temperature process. Conventional gasifiers, such as General Electric’s and Shell’s, rely on temperatures around 1,500 ºC to turn finely ground coal into a combustible mixture of carbon monoxide and hydrogen known as syngas. Unfortunately, such temperatures melt ash and other mineral contaminants in the coal, forming a glassy slag that eventually eats through the ceramic tiles that protect the reactors’ steel walls. Even reactors using high-quality coal have to be taken out of service for installation of new tiles at least every three years. They are thus ill-adapted for lower-quality coals that would produce several times more slag.

Clean Technology, Environment, Infrastructure, Innovation, coal

The September issue of the Harvard Business Review presents a well researched yet simple study on sustainability and green for companies wanting to save money and be green.

Here is an excerpt…

There’s no alternative to sustainable development.Even so, many companies are convinced that the more environment-friendly they become, the more the effort will erode their competitiveness. They believe it will add to costs and will not deliver immediate financial benefits. Talk long enough to CEOs, particularly in the United States or Europe, and their concerns will pour out: Making our operations sustainable and developing “green” products places us at a disadvantage vis-à-vis rivals in developing countries that don’t face the same pressures. Suppliers can’t provide green inputs or transparency; sustainable manufacturing will demand new equipment and processes; and customers will not pay more for eco-friendly products during a recession. That’s why most executives treat the need to become sustainable as a corporate social responsibility, divorced from business objectives…..

Please leave a comment if you want the full report.

Environment, Green, Innovation

A regional Power Supply company in India said today it has started operations at the first photovoltaic solar power plant to be connected to the electric grid in India.

The 2-megawatt solar project in Jamuria, West Bengal, was built at the site of an abandoned 6-MW coal-based thermal power plant. DPSC converted its 8-acre site with the help of Green Energy Development, installing 9,000 230-watt crystalline solar modules.

Although a relatively small solar plant by global standards, the companies say the solar plant is the largest in the country. India’s government has set a goal to spend nearly $20 billion during the next 30 years to increase solar installations from almost nothing today to 20 gigawatts by 2020 (see India’s new climate plan aims to set 20 GW solar goal). Among its initiatives, The National Solar Mission is expected to offer a 10-year tax holiday and exemption from customs and excise duties on specific equipment and other project materials (see Inside cleantech India: Kal, Aaj aur Kal!).

The companies spent about Rs 34 crore ($7.1 million) to build the 2-MW solar plant, which is expected to generate 3 million units of electricity a year—enough to power 2,000 rural or 500 urban households. An equivalent-sized coal-based thermal power plant would generate 7 lakh metric tons (700,000 metric tons) of carbon dioxide emissions a day.

DPSC plans to buy the electricity for Rs 5 ($0.10) per unit to distribute to customers in the Asansol-Raniganj belt. The project, which is also set to receive government incentives of Rs 10 per unit, is expected to generate Rs 4.8 crore ($1 million) per year.4

Via CleanTech.com

Electricity, Infrastructure, Innovation, Solar