Solar vehicles receive most of their propulsion energy directly from the sun. They are equipped with solar cells on the surface that convert the sun’s energy on the vehicle into electricity. as electromobiles, they often also carry an energy storage device (usually accumulators) to remain roadworthy even in poor light conditions or cloud cover, at least for a limited time. Electric vehicles that draw their electrical energy exclusively from a stationary photovoltaic system where they charge their energy storage devices do not count as solar vehicles, even if the energy they charge is purely solar; such as z.B. Twike or cityel. These vehicles are grid-connected electromobiles.
With optimum solar irradiation, the high-performance solar cells of the experimental vehicles can provide up to 2.25 kw (nuna2 NL) of electrical power (max. irradiation *area*efficiency compare fossil car with ca. 35-200 kw). solar cars are experimental vehicles for economical automobiles and light weight construction, (see light vehicle and low energy vehicle).
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[solar races and solar rallies
Various organizations around the world regularly organize races with solar cars.
The highlight is the race across australia, the world solar challenge, which takes place every two years. The top finishers achieved a distance of about 3.000 km total average speeds of over 100 km/h (as of 2005); only driven in broad daylight and not counting the rest of the time. the dutch solarmobil set a record of 830 kilometers in one day nuna II in october 2003. 1993 also the unmanned solar airship LOTTE2 took part in the rallye.
The vehicles require only 0.17 liters of gasoline equivalent for 100 km at a weight of 300 kg. This is the most important feature of these solar vehicles, the speed is limited by the maximum speed allowed on public roads. On 25. September 2005 saw the launch of the 7. World solar challenge, won for the third time in a row by the NUON team with the NUNA III solar vehicle, and for the first time the "dream limit" has exceeded 100 km/h average speed (reached more than 102 km/h, see weblink below).
The "north american solar challenge is a similar race, also biennial.
Other internationally important competitions are:
- American solar challenge – USA
- World solar car rally – japan
- Sunrace – australia
- Canadian solar discovery challenge
- Dream cup solar car race suzuka – japan
- Solar car race phaeton hellas – greece
- South african solar challenge – south africa
The sky ace TIGA, a solar vehicle from ashiya university, japan holds the land speed record for solar vehicles. In 2005, it reached 150 km/h in greece, on 19. September 2006 in taiwan 165 km/h.
[edit] solar boats
photovoltaics is also used for boats. Thanks to its good efficiency over a wide power spectrum, the electric engine is superior to the internal combustion engine in terms of energy consumption. The propulsion power is usually in the range of a few hundred watts to a few kilowatts. In contrast to electric boats, solar boats use direct solar radiation as a source of energy. Mostly accumulators serve as buffers. Thus they have theoretically – similar to a sailboat – an unlimited range. In contrast to sailboats, they are also particularly suitable for navigating canals and rivers. A combination with grid chargers and inverters can be useful. In this concept, the boat is connected to the grid at the berth. The battery is charged until it is full and then the energy of the solar generator is fed into the grid. Most solar boats equipped in this way feed in more energy than they consume. For longer distances on open waters or seas, however, additional propulsion systems such as sails, wind or diesel generators are usually necessary. The latter is useful in cold environments to heat at the same time. For small boats, muscle power drives instead of diesel generators have also proven successful. Due to their low power density, solar drives are not suitable for applications with permanently high power requirements (z.B. High speeds).
Since around 1985, solar boats have been a topic of discussion in europe as travel/residential boats: in 1989, the trimaran basilisk succeeded in making a round trip from basel – koblenz – trier – saarbrucken – strasbourg – basel, and in the winter of 1990/1991, a trip from basel to denia, southern spain (2.000 km). By 2006, matthias wegmann had covered around 50,000 km with a number of other experimental boats – also combined with pedal drives. example: a cabin cruiser (8 x 2.5 m, 2 t) can be moved electrically at 2 kw at 10 km/h, while a standard gasoline engine requires 2 l/h to do so. at reduced speed, the difference in efficiency becomes even more pronounced.
Solar boats or solar ships have been used in everyday life since 1995 [1] . On some inland waters (e.g.B. Alster/hamburg, bodensee, spree/berlin) they are used as pleasure boats or ferries. The "spree-shuttle (former. "Gaienhofen") laid 5 solar cells in the period from june 2000 to october 2003.000 km back. In the summer of 2003, the solar ship required only two charges from the power grid. In total, more than 4.000 passengers carried.
From april 2006 onwards, two solar-electric powered boats were used on the weser river in hameln, Germany, and were very successful for tourists. The number of visitors continued to increase in 2007 and the response was very positive throughout. Hereby the concept of this technology was successful and the way was cleared for further solar boat projects. the continuation of this tourism project in 2008 will be carried out by new and technically up-to-date boat models.
In early december 2006, the sun21, a solar catamaran built in switzerland, took off from seville for the first atlantic crossing of a solar boat [2] . After a stopover on the canary islands, the boat and its 5 crew members arrived on 2. February 2007 the port of le marin on martinique in the caribbean and on 8. May the target new york. The project initiated by martin vosseler.
With PV-H2 hybrid technology equipped electric or. Solar boats use a combination of photovoltaics and fuel cells, the latter powered by hydrogen, which in turn is produced reversibly with the aid of solar cells. A world-first prototype, the "solgenia, is being developed as a research vessel at the university of constance and has been in practical operation on lake constance since the beginning of 2007.
[edit] space travel
A small but quite successful niche has been conquered by solar vehicles in unmanned space flight. they have already been used to explore the surface of other celestial bodies. The lunochod 1 and 2 landers explored the moon as early as the beginning of the 1970s. The solar mobiles sojourner, spirit and opportunity carried out investigations on mars. The solar cells supported the accumulators carried along resp. loaded them again. the mission of lunochod 2 had to be terminated after the solar cells were covered by swirling dust.
The solar ion propulsion system uses the electrical energy from solar cells to accelerate an ionized gas and propel spacecraft with the recoil.
[edit] solar bicycles
special constructions are particularly suitable for the attachment of solar cells. However, commercial versions are not expected until the efficiency of mass-produced products exceeds 20 percent. The illustration shows an experimental bicycle with 8 ultracaps from the 12V solar cells without charge controller up to approx. 20V can be charged.