Nanosolar, solar energy at $1 per watt

Nanosolar is a Silicon Valley start-up that manufactures thin film solar panels.  The video above shows Nanosolar's method of manufacturing solar cells by printing photovoltaic material directly upon sheets of aluminum at a rate of 100 feet per minute. Nanosolar claims that using this method they can manufacture solar cells at $1 per watt. If they can really produce solar cells at $1 per watt, it will represent a huge shift in energy economics. Nanosolar estimates that at $1 per watt, the over all cost of a system will be $2 per watt compared to a coal plant which has a cost of $2.10 per watt.

The average home uses about 8,900 kilowatt hours in a year. If a solar panel could generate electricity 24 hours a day, a one kilowatt solar panel would be sufficient to power the average American home. However, every place on earth averages 12 hours of daylight and many days are cloudy. Assuming a panel can average 6 hours of sunlight a day, a four kilowatt panel should handle the power needs of an average home. This type of array would generate excess electricity during peak hours on hot sunny days when electricity is in high demand which could be sold back to the grid in exchange for credits for energy used from the grid on cloudy days or at night.

At a price of $2 per watt a four kilowatt system would cost $8000. The cost of electricity, depending on where you live, is about $.12 per kilowatt hour. The average homes spends about $1068 on electricity per year.  So over the course of a decade, a Nanosolar system would save the average home $2,600 excluding financing charges and assuming that energy prices do not rise. If the panels last 25 years, as warrantied by the company, the average home would save approximately $18,700. However, energy prices are almost certain to rise and so the actual savings would be greater.

Unfortunately, it is impossible to verify if Nanosolar can actually manufacture at $1 per watt.   The company is not disclosing prices and claims that current manufacturing capacity is sold out for the next 12 months.