By Lena Babaeva Coradini

This Top 10 Renewable Energy News Stories list is from last week, but it highlights some great stories: 

1.  Finding a Better Way to Harvest Algae - Algaeventure Systems has invented the HDD dewatering system, which it claims reduces the cost of harvesting, dewatering, and drying microalgae by over 90% -- a major development for algal biofuels.

2.  Hexicon's Innovative Floating Wind Platform - Swedish-based Hexicon has developed a unique offshore wind design in which the wind turbines sit on top of a floating wind platform.  Hexicon claims the design allows for easier maintenance, less environmental damage, and offers more flexibility.

3.  Nissan Says It Has No Competition in the Electric Vehicle Market - Look out auto manufacturers, Nissan has come out swinging.  The company says that no other car-maker is better prepared to tap the burgeoning electric vehicle market than Nissan.  The Nissan Leaf, set to debut in 2012, already has 56,000 orders.

4.  Solar Thermal Water heating System Installed in Idaho Restaurant - The Homestead Family Restaurant in Blackfoot, Idaho has set an example for the rest of its community.  The restaurant recently installed a solar water heating system that it estimates will reduce electricity costs by $500 per month.

5.  Investors Optimistic About Clean Tech Sector - KPMG LLP recently conducted a survey of 200 bankers, investors, and venture capitalists.  The survey showed very positive results for renewable energy.  77% of the respondents said they expect venture capital investment in clean energy start-up companies to increase in 2010 compared to 2009.

6.  New Study Speaks Out Against Industrialized Nations Outsourcing Emissions - In a shocking indictment, a new study from the Carnegie Institution For Science outlines how industrialized nations reduce their emissions by outsourcing work to developing nations.

7.  Renewable Energy Companies Flocking to Ontario - As a result of an incredible set of renewable feed-in tariffs and its proximity to the United States, Ontario has become an extremely desirable place for renewable energy companies to set up shop.

8.  Valero Betting on Ethanol's Future - Analysts are predicting ethanol prices will arise from the ashes this year -- some are forecasting a spike of as much as 20% by the summer.  If the analysts are right, Valero Energy Corp. is set for a big pay-day, as it has been aggressively expanding its holdings in the U.S. ethanol industry since it entered the market last year.

9.  New GM Technology Could Turn Exhaust into Energy - General Motors is currently developing the Lightweight Thermal Energy Recovery System.  This technology has the capabilities convert waste heat emitted from car engines into electricity.  This captured heat could power a hybrid battery or even replace the vehicle's alternator altogether.

10. Oil Executives Warn Against Renewable Energy - At the CERAWeek energy conference, executives from Saudi Aramco and ConocoPhillips not only spoke out against the global enthusiasm about alternative energy sources that continues to multiply by the day, but they also made light of it.

Great rundown of stories that may have been missed in last week's news stories.