low-cost solar roof

Taking the solar roof to new heights, an Argentine scientist has designed a low-cost solar roof that is more sophisticated than any other I've seen, performing both heating and cooling functions. As one of the Treehugger post's commenters has noted, the devil is in the details - but I like the idea that this system can perform more than one function, and still be affordable.

energy islands

Sounds a bit like outposts on the moon, but architect Alex Michaelis is proposing human-built floating islands to produce energy, hoping the idea will win Sir Richard Branson's Virgin Earth Prize. The self-contained settlements would be run by small populations complete with farming, water desalination plants, and whatever else is needed to keep the islanders happy. Regarding the effort needed to produce the world's energy using this method, I find his motivation curious:

Michaelis, who is working together with his father Dominic, an engineer, estimates that each island complex could produce 250MW. It would take more than 50,000 installations to satisfy current world demand for energy, but Michaelis senior believes it is not impossible. "If we consider that we are at war to find a new form of clean energy, wartime effort in world war two produced vast numbers of planes, tanks, ships and other armaments on both warring sides," he said. "20,300 Spitfires alone were built, making the construction of more than 50,000 of these plants seem a reasonable number."

where the sun shines, there's energy

Part of the task of increasing the use of renewable energy is finding ways to tap unused sources that otherwise just go to waste, like hot water from your shower going down the drain. Here's another one from the Netherlands: using the sun's energy as it heats up road surfaces.

A latticework of flexible pipes, held in place by a grid, is covered over by asphalt, which magnifies the sun's thermal power. As water in the pipes is heated, it is pumped deep under the ground to natural aquifers where it maintains a fairly constant temperature of about 68 F. The heated water can be retrieved months later to keep the road surface ice-free in winter.

This would reduce the cost and environmental impact of using salt on roads. The system is being used to heat buildings, and can pump cold water from a separate subterranean reservoir to cool buildings on hot days. Apparently the heating function is effective even with predominantly cloudy weather.

methane hydrate - energy hope for chindia

As permafrost melts, it releases methane, contributing to atmospheric greenhouse gas concentrations. If this gas could be captured and used as a fuel source, the carbon would still end up in the atmosphere, contributing to global warming, but at least it would be of of some benefit first.

I haven't heard of a financially viable method to trap methane from permafrost, but methane hydrate has recently been found frozen in layers of clay and silt off the Chinese coast, where it may be feasible to extract it by drilling. Indian researchers have also found thick layers of the stuff in sub-ocean ash sediments. Potentially, this is a massive new energy source that China and India would love to get their hands on.

Unlike the methane in permafrost, which is vulnerable to release from melting, the gas under the ocean is relatively stable, so extracting and burning it as fuel can add significantly to GHG concentrations. Now German researchers are looking at a way to mitigate the impact. What they propose is to capture carbon dioxide from coal-fired power stations, ship it to methane extraction wells, and pump it down to the trapped methane. It has been found that under the right conditions, carbon dioxide can penetrate the ice, displacing the methane. The methane is released up the well, and the carbon dioxide remains behind, trapped in an ice cage. The method is not ready to use, but researchers are hoping that funding will enable development of this approach to carbon sequestration before methane extraction becomes big business.

RUrbanism - transformation in India

There are a number of plans, in various states of preparation and implementation, for new cities to be developed on principles that establish new levels of sustainability performance. Just as important is how to improve the performance of existing cities.

This is not new, but new to me: an archived post on WorldChanging brought to my attention by a colleague, about RUrbanism. This essay about the Goa 2100 Project suggests a way for existing cities - particularly, but not exclusively in developing countries - to transform themselves to perform more sustainably. This planning project for the capital city of Panjim, in the Indian state of Goa, addresses the relationship between growing urban centres and their rural hinterland.

RUrbanism is a design framework that offers a new way to look at "everything from urban form, to resource flows, to the mix of paid work and unpaid community engagement that comprise a vital community. It also offers powerful, quantitative methods for planning that transition, from finding the optimal size and shape of built infrastructure to financing the process of rebuilding over several decades."

The project looked at things like optimum densities, principles for infrastructure design, use of local materials, and design that is adaptable (and ultimately recyclable). After extensive modelling, the project concluded that the city of Panjim could be sustainably transitioned - affordably - within a period of 30 years. No mean feat, considering the lifecycle of urban infrastructure.

But perhaps the most important challenge that Goa 2100 identified was the transformation of current institutions and systems of governance. The sustainability transition clearly new values and ethics: sufficiency, equity, and the ethic of using a minimal throughput of matter, energy and information with the least impact on nature society and future generations. These were identified as key goals for the project, and they require changes in how a society like Goa governs itself.

cooling buildings the smart way

Centralised refrigeration systems have the potential to achieve the dual benefit of reducing total energy consumption and reducing demand during peak periods.

A station at the Yalongwan Holiday Resort in China is being built by Hainan Guodianhuade Energy Investment Co. Ltd. to reduce the use of traditional air conditioning. It will make ice during the night, when energy demand is low, and send cooled air to buildings during the day. The project, upon completion, is projected to save 15 million kwh of electricity and 2 million cubic metres of liquefied petroleum gas every year, compared with traditional decentralised cooling systems.

eat this, dude

Airborne pollutants are eating away at stone buildings - national treasures - in Italy, and now there's a technology that can be used on the outside of buildings to turn pollutants into harmless nitrates and sulphates that can be washed away with rainwater.

The key to the solution is a natural process known as photocatalysis, which, in the presence of light, breaks down carbon monoxide, nitrogen oxide, benzene, and other pollutants. It achieves this by dramatically speeding up the oxidation that converts those substances into less harmful compounds, such as water, carbon dioxide, and nitrates. The photocatalyzer TX Active was developed by researchers at Italcementi Group. It is essentially a blend of titanium dioxide, and can be incorporated into paint, plaster, and mortar, as well as cement. In turn, the compound can be used almost anywhere in an urban environment, including repainting walls, plastering new and older homes, and repaving streets when needed.

[Source: Pristine Planet]

baking soda to the rescue

Carbon capture and storage has been suggested to mitigate the impacts of coal-fired power stations, but this entails considerable capital and risk, particularly if it is stored as compressed gas, as some are proposing. An alternative is to use the carbon in other products.

Joe David Jones, the founder and CEO of Skyonic, has come up with an industrial process called SkyMine that he claims captures 90 percent of the carbon dioxide coming out of smoke stacks and mixes it with sodium hydroxide to make sodium bicarbonate, or baking soda. The energy required for the reaction to turn the chemicals into baking soda comes from the waste heat from the factory. The baking soda can be sold, or stored underground in disused mines - considerably easier than storing carbon dioxide gas.