Would a solar powered flashlight be useful?
442134
Sure they can be useful.  If you're camping where you don't have access to electricity, for instance.\n\nThere are problems of course.  A bright flashlight uses a lot of power and there isn't enough surface area for solar cells to capture much energy throughout the day.  So you get a few minutes of use from a whole day of charging.  The newer LED flashlights go a long way to fixing that, though.  And usually it's not a problem because you don't usually need flashlights every night for long periods of time.\n\nAlso you really would want to charge the flashlight outdoors because there isn't very much energy in indoor light.  Sure it's enough to charge a tiny calculator battery, but flashlights need a lot more.  But leaving it outdoors exposes it to the heat/cold/rain/snow/wind/thieves.\n\nDon't store it in the toolbox. :)
656604
You could focus sunlight from a bundle of light fibers using a lens and really burn things up.\n\nFocused sunlight can burn holes through steel plates.\n\nAny amount of sunlight falling on something will heat it.\n\nYou only need a simple thermometer to check it out.
1040483
runs with solar energy
574849
I think I would go with windmills, solar panels might be too much technology for an Amish technology.
1183857
You're going to want something that gives your battery less than about 130 W or you'll cook it.\nThat would be about 150 to160 W panel depending on brand and how it's connected.\n\nYou may want to oversize this a bit given that your panel won't be collecting all the sun possible mounted to the back of a scooter.  If you're not overly concerned about battery life, try a 200 W panel (gotta warn you though - it ain't gonna be small)
1174419
If you think on the lines of the principle of using your bicycle to make the light work which is attached to the back wheel...then how about if you attach a paddle to the the dynamo place it in the house roof drain pipe. In theory when it rained the force of the water running down the drain pipe would generate enough energy to turn the dynamo.\nHence you have solved how to make current with a dynamo at home....brilliant!!!!!!
207295
Actually, just point you camcorder in the direction of the Sun, however, don't look through the camcorder.  When you see the video, the Sun can only be so bright and won't hurt your eyes as you look at the video.
1139758
Yes, it could and we will harness this form of power in the future.\nHowever, please remember that lightning is used by nature as a means of providing food for the soil bacteria with nitrites and nitrates. Like anything else, if we become greedy and harness all the energy, we may create environmental problems, such as food production. This is in parallel with harnessing water in a river, and then holding up all the water to generate electricity and not let other creatures that depend on the water flow have that water.
1061994
Considering that sunlight could be considered a "cosmic ray", and there are a few different means of producing electricity from sunlight, the answer is yes.
988898
PV tech is expensive and only works when the sun is shining. Not the best solution when we have a delivery infrastructure for bulk power. Don't forget about all the batteries a solar set-up needs. Where do they go when they no longer hold a charge?\n\nNuclear is the best solution.
308968
if you are referring to creating electricity from uv light then any standard photovoltaic panel will do the job.  Depending on what photovoltaic material you use the efficiency will change, but because much UV is fairly close to the visible spectrum most will give you decent collection.
239071
get a solar panel and hook it up to your car.
895528
i dont know about you, but my phone is in my pocket all of the time, unless I am actually using it. so a solar powered one wouldnt do much good, as it would never see the sun.
176368
While the above is true, don't give up. U can still get power from the sun to power your computer.\nAlso, there are many prototypes in the works.\n\nMicro-Star unveils solar-powered notebook computer:\n \nThursday, January 12, 2006 \n\nA Taiwanese company has developed a solar-power notebook computer to save computer users the trouble of charging batteries by plugging them in, the company said yesterday. \n\nMicro-Star International Co said it spent a year to develop the first-generation solar notebook computer, Solar NB, and is now developing the second-generation Solar NB. \n\n"Solar NB is a notebook computer with a solar panel on its top. The first-generation Solar NB can operate on solar light power for half an hour but it takes the solar panel half an hour to collect that much power," Micro-Star International's marketing manager Chen Chien-hung said. \n\n"For the second-generation Solar NB, we will use satellite solar power which is more effective but also more expensive," Chen said. \n\nThe 12-inch first-generation Solar NB costs NT$55,000 (US$1,700). The second-generation Solar NB will cost NT$80,000 and is expected to be able to operate on light power for at least four hours. \n\nChen said that although Solar NB can be used outdoors, the main purpose of developing Solar NB is not for outdoor use, but for indoor use, and the solar panel does not collect solar power, but light power. \n\n"We want to allow people to use notebook computers when they travel in an aircraft or train, either by relying entirely on light power or using both light power and the battery when the light in the plane or train is dim," he said. \n\nMicro-Star International unveiled a pair of Solar NBs at the 2006 International Consumer Electronics Show last week in Las Vegas, but will not market it until the product is more mature. \n\n \nhttp://www.partsonsale.com/desktopcompsol.html\n\nhttp://www.solarpower.org/art4.html
117796
I'd find something in my purse to light my way to get the heck out of there!  (cell phone, lighter, compact mirror w/ light)
117670
A method for making really cheap solarcells from sand and a way to transport the elctricity the generate without any loss. The amount of energy that falls on the Sahara during a year could cover the worlds entire energy needs 50 times over even using standard photocells that convert only a few percent of the light to electricity. With such an abundant and cheap energy source we could replace ALL other energysources as electricity can be converted to any other form of energy and fuel. We could even keep gasoline cars because gasoline could be manufactured from CO2 (from the air) and hydrogen (from water). There would be alot less pollution if I could invent these things.
515649
http://www.darvill.clara.net/altenerg/solar.htm\n\nThis is a favorite source of future energy for many people, comforted by the thought that it is unlimited. But, quite the contrary is true. The Sun will exist for a long time, but at any given place on the Earth's surface the amount of sunlight received is limited--only so much is received. And at night, or with overcast skies, or in high latitudes where winter days are short and for months there may be no daylight at all, the sunlight received is very limited at times. Direct conversion of sunlight to electricity by solar cells is a promising field, but the amount of electricity that can be generated by that method is not great compared with demand. The conversion efficiency is low, about 12 percent with present technology.\n\nSolar energy in quantity requires huge installations. It has been estimated that an area of 60 square miles in relatively clear central Oregon would have to be covered with solar cells in order to meet the present electric needs of that State. About 10% of the cells have to be replaced each year. But the big problem is how to store significant amounts of electricity when the Sun is not available to produce it. That problem remains unsolved. The statement that "solar energy will not make next century's electricity" is probably right. And the end product is electricity--a very limited replacement for oil.