In new growth markets particularly, where mobile networks are expanding into rural areas, advanced infrastructure such as a power grid is not always reliable or readily available and base station sites need to run autonomously. A sustainable alternative is to use renewable energy sources such as wind and solar power.

Traditionally, the energy used to operate these sites has come from diesel generators that not only create CO2 and other harmful emissions, but also require regular re-fuelling and skilled maintenance work, which leads to additional travel and maintenance costs for the operator. Most importantly, the cost of diesel is high and is expected to rise in the future.

“A sustainable alternative to power remote base station sites is to use renewable energy sources such as wind and solar power. By 2011, our first choice to power these sites will be renewable energy”, said Anne Larilahti, head of environmentally sustainable business, Nokia Siemens Networks, in a speech given in the Green Forum industry event in Beijing today.

Nokia Siemens Networks’ autonomous sites can be configured to best suit the environment of the site. In the sunniest parts of the world, photovoltaic cells can be used to convert sunlight to energy and provide the electricity needed to operate the site, and often solar panels are complemented with wind turbines.

“Solar and wind technologies are mature, they have a long life time, their operational cost is almost nonexistent and the capital expenditure required is decreasing. The lowering investment cost and the increasing prices of fossil fuels work together to improve the business case of utilizing renewable energy sources” said Larilahti.

The conditions of each site are studied in order to decide on the optimal configuration of solar panels, wind turbines or hybrid combinations. With its network planning Nokia Siemens Networks finds the optimal solution for each site. Sophisticated network design takes into account local solar and wind conditions, site landscape and other factors, to create radio access networks that need minimal external support.

Wind and solar powered sites need minimal maintenance and they are also relatively easy and inexpensive to install. Renewable power sources are an excellent choice for many emerging markets, because they contribute to the low total cost of ownership that is vital for providing affordable communications services to subscribers. With increasing oil prices, payback times on the investment to hybrid solar-wind powered base station sites are continuously decreasing. Considering capital expenditure and operational cost, an autonomous site powered by renewable energy sources pays off after 2 – 4 years in a good sunny and/or windy location.