Reportage: Solar Base Station
This year MegaFon transferred one of its base stations (BS) in the North Caucasus (North Caucasus Federal District) to an alternative power system - the electricity for the station’s operation is generated from solar energy.
A little about the base station
1. Built in 2006 on Mount Tash-Bash (643 m above sea level).
2. Coverage: the villages of Lower and Upper Kazanishche, the total population of about 15,000 people.
3. Food - a normal power line plus a gas generator in case of emergency.
Why did you decide to transfer to alternative energy sources? The reason is simple: constant problems with the electricity supplier - up to 20 accidents per month. Of course, the gas generator secured, but under such conditions the batteries very quickly failed, they had to be replaced every six to eight months.
It is not surprising that MegaFon decided to eliminate this problem once and for all by installing an alternative power source. Experience has already been - in Tajikistan, some of the TT-Mobile operator's BSs (owned by MegaFon) are powered by solar panels.
The most difficult moment in the design was the calculation of the area, the angle of inclination of the solar panels depending on the geographical coordinates of the object, the power of solar radiation in the context of year-round use, the maximum and average required load power.
The required power of solar panels was calculated on the basis of many factors: time of year, time of day, weather conditions and geographical location. Evaluation of these factors was carried out both for the minimum - for the worst month (for this area - this is January), the average values - for most of the year (February-November), and for the summer maximum (for this area it is July).
Choosing a system The system to be
installed had to meet a number of conditions ensuring uninterrupted and trouble-free operation of the base station equipment. The most important of them:
- stable supply voltage of 40-60 V DC;
- required load current 80–100 A;
- the necessary time of operation of the equipment in the dark from battery;
- economically sound payback period for equipment.
The facility is located in a convenient area for installation; access roads are of federal and republican significance.
Delivery and installation of equipment did not cause any particular difficulties.
system consists of The system consists of panels with photovoltaic cells, a solar controller, a hybrid power supply system, and batteries.
- Panels Now 42 solar panels are functioning at the facility, each with 72 photocells. The total area of the panels is 53 square meters. m, they are able to generate up to 5 kW. The panels can operate at temperatures from –40 to +85 degrees Celsius.
The surface of the panels is protected by tempered glass, the strength of which is enough to prevent all possible damage with the exception of, of course, acts of targeted vandalism.
- Batteries The battery capacity is enough for about 12 hours of battery life.
Naturally, the connection to the mains is preserved, but only as a backup power channel - with a possible drop in battery capacity below 70% in the absence of power from the solar panels (dark, cloudy).
The implementation of the project took two months - in the summer of 2014, the BSs were connected to the new energy complex. After conversion, the complex produces standard AC 380V, 50 Hz.
MegaFon experts monitor the status of the station’s power supply system remotely. The duty engineer on duty, if necessary, can make changes to the system configuration through the remote control interface, monitor the condition of the batteries, and monitor other technical parameters of the system. Since July 15, since the launch of the alternative power supply system, there have been no interruptions in the operation of the equipment.
Solar panels do not require special maintenance, that is, the cost of ownership is low. Initially, of course, I had to spend money on their purchase and installation - the cost of the project is comparable to the cost of building a high-voltage transmission line. It's no secret that the main disadvantage of this alternative energy source is the high price. But this project will pay off in two or three years.
What will happen next?
We look forward to the massive use of such technologies in the future. This requires a qualitative breakthrough in the cost of producing solar panels (and, as a result, their final cost) and / or an increase in the efficiency of converting solar energy into electrical energy.
It is hoped that this will happen in the near future. In August of this year, the laboratory of the University of Liverpool announced that it had developed a new, much less costly method of producing a certain type of solar cell. The cost of their release can be reduced by replacing the toxic substances used in the production with those found in regular bath salts. More than 90% of solar cells are made of silicon, about 7% - of cadmium telluride. The latter are thinner and lighter, but their production uses toxic and expensive cadmium chloride.
Scientists from Liverpool have figured out how to replace it with non-toxic magnesium chloride. According to the head of this research project, Dr. John Major, this will help reduce the cost of solar energy to fossil fuels.
Until this happened, there are few base stations for which the construction of such an energy complex would be justified. MegaFon plans to install solar panels on two more BS in the near future.
Friends, if you have any questions, we will be happy to answer them in the comments.
PS: The base station has now become so special that they decided to give it a name - the station is named after Anvar Hamidov, a famous Kumyk poet, translator and teacher who was born in 1924 just in the village of Lower Kazanishche.