We carry solar photovoltaic panels rated at 270 watts per panel, along with all of the electrical controllers, batteries and regulators to provide DC power to run greenhouse lights and pumps.  These panels can be  chained together to meet almost any need.  

We estimate that energy savings will pay for the solar cells in less than 30 years assuming an electric cost of $0.10 per kilowatt hour.  However, the real advantage of solar cells is that they allow for independence from the electrical grid.