Newsletter Archive

Polycarbonate Roof

A customer wanted to place his modules under a polycarbonate roof to discourage theft. Steve Ross measured the output under a sheet of it and it didn't show any significant decrease of power output. We are always interested to share your experiences and questions, so don't forget to send them in.

UV Water Sterilisation

A customer recently asked me for more information about this topic which is reproduced below:

Water borne diseases are a leading cause of sickness and death, particularly in children living in undeveloped countries.

The main methods of water purification are boiling, chlorine and ultra violet (UV) sterilisation. Boiling is effective but uses a lot of energy and is not practical on a large scale.

Chlorine is very cheap, however it is corrosive and poisonous and needs to be used according to rigorous engineering standards.

UV sterilisation is economical as well as being quite safe and simple to use, even in remote village conditions. It is used by many hotels, food and beverage manufacturers for ensuring their water quality. Their operation basically involves passing the water through a cylinder with a UV fluoro type light inside a given flow rate.

Many different sizes of sterilisers are available; the smallest one can purify 1000 litres per hour to 99.999% kill rate (which meets Australian standards for potable water). If only a 99.99% kill rate is required, the unit can purify 1800 litres per hour. These sterilisers are very energy efficient. In a remote area, this unit could produce about 3000 litres per day with a 40W solar panel or 6000 litres per day with an 80W module.