There are many considerations to take into account. Here are just a few.
- Assess the demand and amount of power you'll need to produce and achieve your goal.
- Determine location for photovoltaic system. The size of the location will be the determining factor as to quantity of panels you can install. Note that most panel manufacturers' photovoltaic panels are around 3' x 5' in size.
- Look for panels which have the highest percent of efficiency and yield wattage per panel. Use the wattage per panel to determine quantity of panels required to achieve your goal (demand).
- Look at availability and manufacturer's history as well as life expectancy for panels.
- Determine inverts which will allow you to achieve your goal. The most efficient are micro inverters. These allow each panel to be its own island increasing the array's overall efficiency.
- Research, interview and hire a knowledgeable company within your area to assess your demand based on past energy bills, review your solar envelope and install the most efficient system which fits your budget.
- Look into government grants and incentives for your state. These can reduce the cost of the total system by as much 30% reducing the return on investment between 5-7 years.
Before deciding on installing a photovoltaic system, have an energy analysis performed on your home. Depending on the year it was built, insulation, windows and doors, your home may be losing/using more energy than the benefits you will receive by installing photovoltaic panels.
For more information:
Read "Which brand/model of solar panel works the best? We are thinking about incorporating solar in our new home." a Q&A answered by David Willson.