There is some data available from such systems:

University of applied sciences in Bern (Switzerland) monitores a PV system at Jungfraujoch at 3454 meters above sea level since 1993. Data is available from

http://www.pvtest.ch/index.php?id=415&L=2

Also Fraunhofer ISE operates a field test site at Zugspitze (2650m). Further information is available here:

http://www.ise.fraunhofer.de/en/service-units/testlab-pv-modules/leistungen/aussenpruefstaende

Yes, it will work and we have one of example at Ladhak in India. You may just go through the above

Thank you very much for the information, but I was wondering whether energy storage will be efficient using batteries in high altitudes. If we want to design large solar systems not only for lighting but for small and medium enterprises, then we need to have battery banks. What is the status of energy storage for solar projects?

Yes, it will work even better than in other conditions, because at that altitude there two main factors that produce a very satisfactory performance: usually a very clean atmosphere, and seconly low temperatures

There are applications also in Nepal and in the Alps. Caution should be taken for the co-operation of the inverter with the PV since the open cycle voltage of PVs increases as temperature decreases.

The state-of-art battery bank and interconnecting systems are available. You should take care while estimating the requirement of power and the sizing of PV.

I don´t know the geograhic location, but snow should be taken into consideration. In the Alps in Austria snow covers the PV and either it is cleaned or no electricity is produced.

A solution for such regions are combined solar collectors. Heat and electricity is produced in the same collector. When it snows heat could be taken out of the thermal storage system and warm up the collectors. the snow is melting.

We are working on such systems.

For more altitude better. More solar energy by squar meter

Besides the general answers provided above (better solar resource and lower temperature will improve performance; snow accumulation will decrease it), I'd like to add two important points that may be of importance depending on local conditions:

- Shading due to surrounding mountains can adversely/seriously affect the otherwise better solar resource

- Terrain steepness and non-ideal exposure may cause headaches to design large systems...

I would like to point out one more thing which affects the performance and the lifetime. In principle, the altitude becomes higher, the solar spectrum becomes more blue-rich due to the Rayleigh scattering (note that the cross section is inversely proportional to the wavelength). The effects should be that the conversion efficiency is decreased compared to the standard condition and the lifetime becomes shorter due to the stronger UV irradiation.

Correction; The Rayleigh scattering cross section is inversely proportional to "the 4th power of" the wavelength).

Indeed the spectrum becomes more blue-rich at higher elevations, but not just because of Rayleigh scattering. Higher elevation also means lower aerosol optical depth, whose extinction is also stronger at smaller wavelengths. On the other hand, there is less water vapor aloft (since both aerosols and water vapor are concentrated in the lower troposphere), which means lower absorption in the near IR,. However, the red shift caused by molecular and aerosol scattering is much stronger than the blue shift caused by decreased water vapor.

All these spectral effects can obviously been predicted by the SMARTS code. See

http://www.solarconsultingservices.com/smarts.php

http://en.wikipedia.org/wiki/SMARTS_%28The_Simple_Model_of_the_Atmospheric_Radiative_Transfer_of_Sunshine%29

Like many have answered, the temperature level in high range is much better and within the most suitable range for PV panels and hence, the efficiency is definitely higher than the normal conditions.

There is some data available from such systems:

University of applied sciences in Bern (Switzerland) monitores a PV system at Jungfraujoch at 3454 meters above sea level since 1993. Data is available from

http://www.pvtest.ch/index.php?id=415&L=2

Also Fraunhofer ISE operates a field test site at Zugspitze (2650m). Further information is available here:

http://www.ise.fraunhofer.de/en/service-units/testlab-pv-modules/leistungen/aussenpruefstaende

There are 4 decades of successful experience with high altitude PV systems with many of the earliest PV systems installed on remote mountaintops for repeater stations, etc. The key system design consideration is that at higher altitudes Voc is higher due to the colder temperatures and Isc is higher due to higher irradIance, so overvoltage and overcurrent protection need to be appropriately sized for these conditions.

Low temperature in mountain high is typically good for Solar PV as its efficiency goes high. However we experienced at certain places, cloudy weather on the mountain most of the time in a year doesnot help at all. 

So short answer is it really depends from place to place.