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The American Chemical Society has a post on the possible use of hemp in creating supercapacitors - Could hemp nanosheets topple graphene for making the ideal supercapacitor?

David Mitlin, Ph.D., explains that supercapacitors are energy storage devices that have huge potential to transform the way future electronics are powered. Unlike today’s rechargeable batteries, which sip up energy over several hours, supercapacitors can charge and discharge within seconds. But they normally can’t store nearly as much energy as batteries, an important property known as energy density. One approach researchers are taking to boost supercapacitors’ energy density is to design better electrodes. Mitlin’s team has figured out how to make them from certain hemp fibers — and they can hold as much energy as the current top contender: graphene.

“Our device’s electrochemical performance is on par with or better than graphene-based devices,” Mitlin says. “The key advantage is that our electrodes are made from biowaste using a simple process, and therefore, are much cheaper than graphene.”

The race toward the ideal supercapacitor has largely focused on graphene — a strong, light material made of atom-thick layers of carbon, which when stacked, can be made into electrodes. Scientists are investigating how they can take advantage of graphene’s unique properties to build better solar cells, water filtration systems, touch-screen technology, as well as batteries and supercapacitors. The problem is it’s expensive.

Mitlin’s group decided to see if they could make graphene-like carbons from hemp bast fibers. The fibers come from the inner bark of the plant and often are discarded from Canada’s fast-growing industries that use hemp for clothing, construction materials and other products. The U.S. could soon become another supplier of bast. It now allows limited cultivation of hemp, which unlike its close cousin, does not induce highs.

The ABC has an article pondering a peak in Chinese steel consumption and the impact on Australian iron ore miners - Peak steel could leave Australian iron ore miners in the lurch.

Theres a disturbing new phrase being uttered by bears in the resources game - "peak steel". And its a very different phenomenon to the "peak oil" theory, where supply dries up and energy prices soar.

Peak steel is all about too much supply, not enough demand and tumbling prices. While not conclusive proof, the recent fall in iron ore prices is showing there is a significant rebalancing of supply and demand going on. Since the start of the year spot prices are down more than 20 per cent. ...

In a recent report, the analyst team from brokers CLSA noted that "peak steel demand would be seen this decade rather than next." The CLSA research cited factors such as "the slowing pace of urbanisation and demographic trends which are going sharply into reverse."

Increasingly Chinese developers are reducing their land banks and building smaller apartments, with floor-space construction falling 27 per cent in the first three months this year. Overall, CLSA forecasts a 37 per cent decline in private property floor-space sales between 2013 and 2020.

CLSA says steel consumption in the property sector is likely to peak this year, and a similar scenario is developing in infrastructure. "We also forecast infrastructure steel consumption to peak this year, with steel demand from road and rail construction to decline," the analysts noted.

TreeHugger has a look at a use for the glut of timber from trees killed by pine beetles - Interlocking Cross Laminated Timber Could Use Up Square Miles Of Beetle-Killed Lumber, and Look Gorgeous, Too.

The Mountain Pine Beetle is killing trees across North America, including up to 44% of Colorados forests. If there was any infrastructure investment to be made right now, I would have thought it would be to set up a pile of cross laminated timber factories fast, and put people to work churning out panels at a standard size and stockpiling them; CLT is strong, fire resistant, it sequesters carbon dioxide and it makes very pretty buildings.

At the University of Utahs Integrated Technology in Architecture Center, (ITAC) they are working on a modification of the design of CLT for the American market, namely figuring out how to make it cheaper.

Technology Review has a look at a new approach to CAES energy storage - Compressed-Air System Could Aid Wind Power.

SustainX, a startup in West Lebanon, New Hampshire, has received $20 million in venture capital to test its compressed-air energy storage technology on a large scale.

The technology could allow for a wider use of compressed-air storage, which in turn could make renewable energy more attractive, since it would allow wind power generated at night to be stored until daylight hours, when demand is higher. If its successful, the technology could decrease the need to build natural gas plants to supply peak power demand.

The need for storage is increasing as governments mandate the use of more renewable energy. SustainX has demonstrated a 40-kilowatt prototype and is now completing a one-megawatt system, slated to be deployed next year with the power company AES.

In conventional compressed-air storage, electricity is used to compress air, which is stored in underground caverns or aquifers. That air is then released to drive a turbine-generator to produce electricity when needed. Such storage costs roughly a tenth of what battery storage costs, but it isnt used much because in large part because it requires a location with underground storage space. SustainXs system eliminates this problem because it can efficiently use above-ground storage tanks rather than caverns.
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Storing compressed air in tanks aboveground is impractical with a conventional turbine-based system because of the large size and cost of the tanks. SustainXs technology reduces the cost of the tanks and other capital costs. "We do aboveground compressed-air energy storage at belowground prices," says cofounder and vice president Dax Kepshire.

The company reduces costs by using pistons, rather than turbines, to generate electricity. Gas turbines can only generate electricity from a narrow range of air pressures. The pistons can operate at a larger range—and because air can be compressed more, the system can store more energy. Whats more, the pistons operate well after the pressure in the tank has fallen too low to drive a turbine.

RenewEconomy has an article on an ANU study of growth in renewable power generation in Australia - Solar, wind could replace all fossil fuels in Australia by 2040.

Solar and wind energy could replace all fossil fuels in Australia by 2040 if their recent rate of deployment is maintained and slightly increased over the next 27 years – delivering the country with a 100% renewable electricity grid “by default” as early as 2040.

The stunning conclusions come from research from Andrew Blakers, the director of the Australian National University’s Centre for Sustainable Energy Systems. It notes that nearly all new electricity generation capacity in recent years has been wind and solar photovoltaics (PV), and demand has also ben falling since 2008.

Blakers says that if this situation continues then Australia will achieve renewable electricity system by 2040, as existing fossil fuel power stations retire at the end of their service lives and are replaced with renewables.

And the cost will be no greater than having fossil fuels because, as Bloomberg New Energy Finance notes, wind is already cheaper than new coal or gas-fired generation and solar soon will be. These are the critical points – because renewables are often painted as expensive when compared to fully-depreciated, 40 years fossil fuel plants. But not compared with the new capacity required to replace ageing fossil fuel fleet.

Blakers says his scenario works even using the more conservative technology cost forecasts prepared by the Bureau of Resource and Energy Economics. These forecasts are being updated, but they came to similar conclusions as BNEF on technology cost trends, just not quite as quickly.

The 100% by 2040 scenario is probably not that much different in scope to current trends. Australia was sitting at around 10 per cent renewables in 2010, and will probably end up with at least 25 per cent by 2020, given current trends on rooftop solar and the fixed 41,000GWh target for large scale renewables.