A characteristic of wave energy that suggests that it may be one of the lowest cost renewable energy sources is its high power density.

Just days after the UK government announced a major new funding campaign to promote ocean and tidal energy technologies in their country, a new, inter-governmental report has been released in the US suggesting that the technologies could be economically feasibly off US shores in the very near future.
The study was carried out by Electric Power Research Institute (EPRI), in collaboration with the DOE's National Renewable Energy Laboratory (NREL) and energy agencies and utilities from six states. EPRI was established in 1973 as an independent, non-profit center for public interest energy and environmental research. Their members represent over 90 percent of the electricity generated in the United States.
Conceptual designs for 300,000 MWh plants (nominally 120 MW plants operating at 40 percent capacity factor) were performed for five sites: Waimanalo Beach, Oahu, Hawaii; Old Orchard Beach, Cumberland County, Maine; WellFleet, Cape Cod, Massachusetts; Gardiner, Douglas County, Oregon; and Ocean Beach, San Francisco County, California, solaraccess.com reported.
The study determined that wave energy conversion may be economically feasible within the territorial waters of the United States as soon as investments are made to enable wave technology to reach a cumulative production volume of 10,000-20,000 MW. (Land-based wind turbines, in comparison, generate 40,000 MW.)
"Wave energy will first become commercially competitive with land-based wind technology at a cumulative production volume of 10,000 or fewer MW in Hawaii and northern California, about 20,000 MW in Oregon and about 40,000 MW in Massachusetts," said Roger Bedard, ocean energy project manager. "Maine is the only state in the five site study whose wave climate is such that wave energy may never be able to economically compete with a good wind energy site."
This forecast was based on the output of a 90 MW Pelamis wave energy conversion plant design and application of technology learning curves that will enable cost savings. The forecast results have convinced the project team of the rationale for investment in wave energy technology research and development, including demonstration projects to prove the feasibility of wave energy conversion technology in actual sea-state environments.
Bedard explained that there are several compelling arguments for investing in offshore wave energy technology. First, with proper siting conversion of ocean wave energy to electricity is believed to be one of the most environmentally benign ways to generate electricity.
Second, offshore wave energy offers a way to minimize the 'Not in my backyard' (NIMBY) issues that plague many energy infrastructure projects. Wave energy conversion devices often have a very low profile and are located far enough away from the shore that they are generally not visible.
Third, wave energy is more predictable and consistent than solar and wind energy, offering a better possibility of being dispatchable by an electrical grid systems operator and possibly earning a capacity payment.
A characteristic of wave energy that suggests that it may be one of the lowest cost renewable energy sources is its high power density. Processes in the ocean concentrate solar and wind energy into ocean waves, making it easier and cheaper to harvest, according to the research team. Solar and wind energy sources are much more diffuse, by comparison.
Wave power was delivered to the electrical grid for first time in August 2004. The electricity was generated by a full-scale, pre-production Pelamis prototype in Orkney, Scotland by Ocean Power Delivery Corporation.
"Wave energy is an emerging energy source that may add a viable generation option to the strategic portfolio," said Hank Courtright, EPRI's VP, Generation. "The bedrock of a robust electricity system is a diversity of energy sources, and wave energy could provide an energy source that is consistent with our national needs and goals."

Australian scientists have successfully carried out the world's first on-the-spot robotic repair of power station turbine blades, opening the way for potentially huge savings for the global energy industry.
Using a robot, a special 'cool' laser and a 'gun' that fires a surfacing compound, a team from the Cooperative Research Centre for Welded Structures (CRC-WS) has demonstrated that damaged steam turbine blades can be totally renovated without removing them from their mounting.
The trial was conducted at TXU Australia's Torrens Island Power station, near Port Adelaide. A collaborative partner with the CRC-WS since 2003, TXU Australia provided financial and specialist expertise to the project.
The treatment involves re-surfacing the blades--each worth $20-25,000--with a metallic formulation that extends their working life almost indefinitely, says CRC-WS chief executive officer Dr. Colin Chipperfield.
By repairing the blades in situ the CRC-TXU team has also slashed the costly downtime required to dismantle, repair and rebuild power station turbine blading, he says.
TXU Asset Manager Ralph Villarosa says it was highly successful. With some further fine tuning of the cladding process the technology offers huge potential for the power industry, e4engineering.com reported.
"De-blading a turbine rotor for repairs is a major exercise both in downtime and cost, and we have found that conventional welding repairs have not met our stringent safety requirements," he says. "We are very hopeful that this technology offers a cost effective solution to refurbishing turbine blades."
Dr. Chipperfield says low pressure turbine blades are susceptible to pitting and erosion from wet steam, requiring replacement at 10-15 years depending on operating conditions. "Our technology makes it possible for them to last the life of the power station.
"This could mean a saving of up to $10 million over the life of the average power station. For Australia, that might well save $200 million or more--and for the world, well, the sky's the limit."
Dr. Chipperfield says the repair philosophy combines three separate technologies --a programmable robot, a direct diode laser and a 'gun' that feeds the metallic compound into the eye of the laser, which deposits it along the edge of the turbine blade. The laser is mounted on a coaxial head that enables it to reach into otherwise inaccessible places due to blade configurations.
The direct diode laser--the only one of its kind in Australia--focuses very intense light on a very small spot on the blade surface. This small spot transmits little heat and so avoids causing distortion or heat-stress to the precision-shaped blades. The laser is also transportable, permitting repairs to be conducted 'in situ' at the power station.
The laser-cladding process deposits a wear-resistant coating with superior bonding and performance over conventional brazed erosion shields. The CRC believes it last 10 times longer than the original metal of the blade itself.
Dr. Chipperfield says the successful trial has triggered intense interest in the technology, both among local power generators and big international firms which make turbines and blades.
"The current challenge is to turn this into a full-blown product and take it to the world," he says, indicating that talks are already under way with a potential commercial partner.
Despite consisting of state-of-the-art robotics and laser technology, he estimates the price-tag of a robot repair rig is not high--a maximum of perhaps $400k--and would pay for itself quickly.
The CRC is already working to establish the size of the potential Australian market for steam turbine repair. It is possible more than half of our 39 power stations could use the technology.
"We're very excited at the potential of this Australian-designed technology, not only for steam turbines, but also for use in gas turbines, boilers, impellers, hydroelectric turbines and other applications."

Exxon Mobil Corp., ConocoPhillips and other oil producers are paying more to operate in Venezuela, Russia and Kazakhstan as surging demand emboldens national leaders to boost royalties and taxes.
Consumers expect producing nations to Ògive oil away,Ó Venezuelan President Hugo Chavez said on Oct. 10. He made the comment in Caracas during his weekly television and radio program, ÒAlo, Presidente,Ó as benchmark futures rallied toward a record $55.67 a barrel.
Now the Chavez government is charging higher royalties that may cost foreign partners in the nation's biggest oil joint ventures $700 million a year. A change last year in Russia's tax policies will boost oil revenue for the government of President Vladimir Putin by $2.6 billion annually.
ÒThe oil price goes up and countries all think, ÔAre we making enough on it?ÓÕ said Gordon Barrows of Barrows Co. in New York, a firm that catalogs global oil and gas production contracts. ÒIt's stirring all around the world,Ó Barrows said in a Dec. 20 phone interview.
The terms countries are dictating may discourage investment needed to keep pace with world energy demand, which grew 3.3 percent last year, the fastest since 1976, according to the International Energy Agency in Paris, Bloomberg.com reported.
The Russian tax increase Òwill change the way in which people make decisions on the margin,Ó Lord John Browne, chief executive officer of BP Plc, said in a Jan. 20 interview in London. Russia passed Saudi Arabia last year as the world's biggest oil producer.

Russian Oil
BP, Europe's biggest oil company, spent $7.7 billion last year to combine its Russian assets with those of OAO Tyumen to form TNK-BP. Robert Dudley, TNK-BP's chief executive officer, said his company is finding profitable investments. More expensive Russian projects such as Arctic drilling are being discouraged, Dudley said in Davos, Switzerland, on Jan. 29.
Russian output may peak in 2008 as tax policies and other actions by the Putin government starve the country's oil industry of foreign investment needed to keep output growing, according to forecasts from PFC Energy Inc. in Washington.
It is getting more difficult for oil companies to find attractive opportunities, said Rick Mueller, an analyst with Energy Security Analysis Inc. in Wakefield, Massachusetts. ÒThere aren't many areas with substantial reserves that are open to exploration,Ó Mueller said in a Feb. 2 phone interview.

Kazakhstan, Trinidad
A law enacted in Kazakhstan in November may help President Nursultan Nazarbayev's government get a bigger share of production from Kashagan, the second-largest oilfield in the world. Patrick Manning, the prime minister of Trinidad and Tobago, the biggest supplier of liquefied natural gas to the US, said in October that he would review the country's production-sharing contracts.
The US is ÒrobbingÓ Venezuela by paying too little for its oil, Chavez said in a Jan. 28 speech in Caracas.
In addition to raising royalties on the oil production ventures, Chavez's government has more recently threatened to sell its U.S. refineries or renegotiate their supply contracts and started a review of 33 oil production contracts state-owned Petroleos de Venezuela SA has with foreign companies.
Energy Minister Rafael Ramirez didn't consult the foreign oil companies that are partners with Petroleos de Venezuela in the oil ventures, according to Stephen Moore, an analyst with Moody's Investors Service in New York. He cited the country's 1943 oil law to justify it, Moore said in an Oct. 19 interview.

Above the Law
ÒNo contracts are above the law,Ó Ramirez said at an Oct. 11 press conference in Caracas announcing the change. Ramirez was tapped this year by Chavez to head Petroleos de Venezuela in addition to the energy ministry.
Ramirez revoked a tax concession that was written into the agreements that created joint ventures in the 1990s to tap the country's reserves of extra-heavy oil. His move raised the royalty rate on the ventures to 16.67 percent from 1 percent.

The Hy-Light needs just two liters of hydrogen fuel to run 100 kilometers.

Swiss researchers say hydrogen as a fuel is slowly coming of age, but warn that it is not yet ready to take to the road.
To prove their point, scientists at the Paul Scherrer Institute (PSI) have been helping develop a prototype car powered by hydrogen. The Hy-Light concept car, developed in collaboration with tyre specialist Michelin, was presented recently in Shanghai.
According to Michelin, the Hy-Light was the most efficient fuel-cell vehicle taking part in the Bibendum Challenge in the Chinese city, beating competition from major car manufacturers in the economy stakes.
ÒItÕs important for us to understand what mobility will be in ten to 15 yearsÕ time since it will affect our core business,Ó said Pierre Varenne of Michelin. ÒSo rather than sit and wait, we decided to develop our prototype.Ó
The tire maker believes that hydrogen-based fuel-cell technology is the best possible replacement for fossil fuels, swissinfo.com reported.

Collaboration
To prove its point, the companyÕs research centre near Fribourg teamed up with the Paul Scherrer Institute, which has been working on fuel cells.
ÒWe recognized it some time ago as one technology that could make mobility more sustainable,Ó said the instituteÕs Philip Dietrich.
Besides its fuel cell expertise, PSI also supplied special condensers. These electrical parts store electricity generated by the carÕs braking, further lowering the Hy-LightÕs hydrogen fuel consumption.
Hydrogen is considered by many specialists to be the fuel of the future. They say it is no more dangerous than petrol, and only produces water vapour as a by-product.
Hydrogen is a very volatile fuel, and to minimise the risk of explosion, it is stored in inter-connected pockets, which prevents large amounts of the gas being leaked in the event of a collision. Dietrich says it will still be some years before hydrogen-powered vehicles hit the road.
ÒThe automotive industry could adopt [hydrogen] fuel cells in ten or 15 yearsÕ time, but it will depend on oil prices and political conditions,Ó he told swissinfo, adding that comfort and price would decide whether drivers chose hydrogen.

Drawbacks
To help car owners make up their minds about fuel-cell technology, demonstration vehicle fleets are already on the road in California, Tokyo and Berlin.
But there are still some hurdles to overcome, according to researchers. HydrogenÕs most obvious drawback is the volume required to store this gas.
ÒYou have to find ways of transporting hydrogen in a vehicle,Ó said Alexander Wokaun of PSI. ÒHowever with more efficient cars, you can consider it as an alternative to gasoline since you need smaller tanks.Ó
Hydrogen is also expensive to produce, two to three times more than petrol. But Wokaun reckons that hurdle is not as big as some people might think.
ÒAfter tax, itÕs a different picture, so there is room for the legislator to give fiscal incentives for hydrogen use,Ó he told swissinfo.

Emissions
Hydrogen itself may be non-polluting, but there is a sting in the tail. It is produced either as a by-product of the coal, oil or gas industries, or by splitting water molecules using copious amounts of electricity, often generated by nuclear power plants.
No current production technique is non-polluting.
ÒIf you produce hydrogen from coal or oil, you still have some emissions,Ó admitted Dietrich. ÒThatÕs why we have to find sustainable ways of producing hydrogen.Ó
Researchers are pinning their hopes on solar-based production, a method Michelin is working on now.
Specialists say that eliminating pollution from the production process will also boost hydrogenÕs chances of mainstream success.
ÒIf you can introduce a method for producing hydrogen cheaply and cleanly, this would probably the best argument for its use,Ó Wokaun told swissinfo.
ÒConsumers will then realize the environmental benefits of hydrogen as a fuel.Ó