No Grid Telecom Base Station Energy Storage System GE sponsored EDSGN 100 Section 018 Prof. Andy Lau Team Taste-E Fall Semester 2010 Brady Alford Jeremy Ogorzalek Ben Wilson Greg Crompton

Problem Statement The objective of the project is to design a telecom cell phone base station system that will be used in a region without a satisfactory energy grid. The system will get its power from sustainable energy sources, such as solar panels, a diesel genitor system, and a sodium metal halide battery. The main focus is making the system use as much green power as possible. The station will be based in a small hut that contains the necessary equipment. Other conditions and complications must be taken into consideration, such as how users will charge the cell phones, precautions against wildlife and weather, and a cooling system for the battery.

Research The Hut –Made with recycled material –Lined with insulation –Fence for protection (12 ft) BTS Station –40 km service range –Transceiver, amplifier, combiner, duplexer

Batteries –97% / 92% efficiency at 300 °C –Small but dense –No maintenance required, 15 year lifetime Charge Controller –Protects battery and directs energy flow –Controls generator and battery

Renewable Energy –Wind conditions in Kenya are not optimal –Solar energy conditions are nearly perfect Nakuru, Kenya –Roughly 300,000 people –63% of Kenyans have cell phones –Many pros of cell phones in Kenya

Analysis Nakuru –.28 degrees south of the equator –Averages 7 kWh/m 2 every day –Perfect for a PV system Photovoltaic Cell Experiment –Angle of solar panels has minimal effect –The cooler the cells, the greater the efficiency

For the previous reasons –Only renewable energy source is solar –Panels set to ten degrees –Not facing directly up because of rain and dirt buildup –Panels are on a rack to keep them from overheating

Determining battery type –Size of photovoltaic system is 6 kW –Generator efficiency is 75% –Use spreadsheet to graph battery size by fuel usage Decided on battery type A2, which had capacity of 25 kWh

Photovoltaic Array –30 GE GEPV 200W solar panels –Each producing 200 watts, 6 kW total –Wired in parallel for a total of 48 volts Charge Controller –Outback FLEXmax 80 –Handles 5000 watts at 48 volts

Generator –Dechron DCG4500 diesel –4500 watts of DC power at 48 volts –Assists in charging the battery –Covered by a custom hood Sound proof and ventilating –External fuel tank, 105 gallons

Battery –GE Durathon Type A2 –Stores up to 24.5 kWh Touch Screen Interface

Special Features Satellite antenna Noise reducing cover for generator Touch screen user interface Barbed wire and electric fencing Ventilated solar panel mounting