And that's not all. We reported recently on this site on the solar powered car making its way around the world. We also covered the concept of solar roads to capture usable energy. We even reported on a sail boat powered with a solar sail. Now the BBC reports that the U.S. military has held a test run in Arizona of a UK-made solar plane, the Zephyr-6. The plane flew for more than three days, running at night on solar charged batteries. The more than 83 hour non-stop flight was the longest of any unmanned aircraft. The Department of Defense is downright giddy over it:

Zephyr has demonstrated that it can cope with extremes of temperature - from the blistering 45C heat found at ground level in Arizona's Sonoran Desert, to the minus 70C chill experienced at altitudes of more than 18km (60,000ft).

The engineers from the Farnborough-based company are now collaborating with the American aerospace giant Boeing on a defence project codenamed Vulture.

This would see the biggest plane in history take to the sky, powered by the sun and capable of carrying a 450-kilo (1,000lb) payload. - BBC

Japan is working on solar powered ships:

Japan's biggest shipping line Nippon Yusen KK and Nippon Oil Corp said solar panels capable of generating 40 kilowatts of electricity would be placed on top of a 60,000 tonne car carrier to be used by Toyota Motor Corp.

The solar panels would help conserve up to 6.5 percent of fuel oil used in powering diesel engines that generate electricity at any given moment. - Environmental News Network

The ship is expected to launch by December of this year at a savings of about 20 tonnes of carbon emissions per year. Not bad. And if it is successful, expect to see entire fleets in the next few years.

Purely solar powered trains aren't here quite yet - though some Italian trains get a solar energy boost for air conditioning, lights and safety systems - but you can see a solar powered miniature train set in the meantime.

What you will be able to get soon are solar purses that capture solar energy to charge your cell phone or MP3 player. Handy for those of us constantly running out of juice for one gadget or another. They are kind of fashionable, too, and certainly more practical than the solar tie.

In rural India, solar loans are going toward solar-powered lights that are a way to scare away cobras and other predators with little cost to operate and none of the harmful side effects of burning kerosene, dung or wood. The Gramathi Grameen Bank is one of the main suppliers of these low interest solar loans, with help from UNEP's Indian Solar Loan Program.

The Solar Electric Light Fund (SELF) works similarly to bring solar energy to rural and poor parts of the world, claiming that "energy is a human right." When you consider that energy is needed for so much more than lights - it is crucial for water pumps, drip irrigation, health clinics, schools, businesses - and that ¼ of the world's population lives without it, they have a point. Plus, J.R. Ewing is on their board! He also happens to own the largest residential solar installation in the U.S., putting co-board member Ed Begley, Jr. to shame.

Solar is on the rise everywhere as 2 large solar installations are being planned in Central California by OptiSolar and Sun Power Corporation.

The plants will cover 12.5 square miles of central California with solar panels, and in the middle of a sunny day will generate about 800 megawatts of power, roughly equal to the size of a large coal-burning power plant or a small nuclear plant. - The New York Times

Pacific Gas and Electric (PG&E) has already agreed to buy the energy as part of meeting California's aggressive standard of getting 20% of energy from renewables by 2010. As the New York Times points out, the plans for the two plants could still run into stumbling blocks with permits and building, but it is certainly another step in the right direction on taking advantage of solar energy potential.

Further Reading:

• Solar Roads. The Power Under Our Feet
• Polar Explorer Raises the World's First Solar Sail  
• Concentrating Solar - Now Safe For Roof Tops
• Will Africa Be The Hub For a Green, Global "Super Energy Grid"?
• Nature Inspires Solar Power Revolution
• Solar Powered Car Arrives on the West Coast to Take in the Sun and Spread Renewable Technology Gospel
• Utah's Solar Fired Furnace to Power California for Less Than the Cost of Coal or Gas
• Solar Thermal Power Coming to a Boil
• First Solar to Build 10-Megawatt Photovoltaic Power Station
• Nanosolar Cheaper Than Coal
• Thin Film Solar Now Shipping