There are many advantages to the solar solution. There is no cabling work involved, the lamps do not require maintenance, they can be installed very quickly, and above all they are eco-friendly. A comparison of the costs involved in installing and operating the lamps (irrespective of future increases in electricity prices) highlighted the financial benefits. The bottom line is that, over an operating period of 30 years, the total costs of a mains-based lighting system would amount to around €100,000 Euro, compared with only €62,000 for solar lighting. What's more, generating the mains electricity needed to power the 17 street lamps would produce 1.7 tonnes of CO2 a year, which have now been saved.
Source: www.oekonews.at/index.php?mdoc_id=1025077 (de)