A Guide to Photovoltaic and Wind Generator Systems
Factors to Consider Before Starting a Renewable Energy Project
A. Make sure your home is energy efficient.
	You can lower your electric bills and help the environment by improving the energy efficiency of your home. In many cases, it may be more cost-effective to reduce your energy use than to install your own generator. If you do install a generator, you will get the most out of your system by using its output efficiently.    Want to know how to make your home more energy efficient? (log on required)
B. Determine if you have a suitable site for a photovoltaic (PV) or wind system.
	For photovoltaic equipment, you will need:
			A location where your PV system will have clear, unobstructed exposure to the sun year-round.
			A southerly orientation for the PV system.
			The ability to install the system on a rooftop or the ground.
	For a wind turbine, you will need:
			A location where your wind system will have clear, unobstructed exposure to wind flow year-round.
			An assessment of wind resources, since wind power is highly site specific. Most systems require average sustained winds of at least 10 miles per hour. Wind Resource Maps are available from the National Renewable Energy Laboratories (NREL) Web site.
			A relatively large area to accommodate the turbine. Wind turbines are generally not suitable for urban or suburban home sites.
C. Review local building codes and zoning regulations that affect your PV or wind system installation.
	Customers are responsible for designing, installing, operating and maintaining their own equipment in accordance with all codes, laws and regulations. For example, your system must meet local building codes and zoning laws and you may need permits or special approval from your community or homeowners' association.
D. Determine the size of your project.
	You should start by reviewing your typical energy usage. This can be done by looking at your past electric bills. You can review your account through Ameren’s eCustomer “View Bill – Current & Past Bill Details” in the My Home section of this site. By reviewing your typical energy usage, you can decide how much power you want to generate yourself, bearing in mind that your PV or wind system will only operate when sunlight or wind is available.    Dealers and installers can provide you with cost estimates and may also help you size your system. To find dealers and installers, consult your telephone directory or check the American Wind Energy Association Web site.    Before choosing a dealer or installer for your project, you should also ask:
			How many years of experience do they have installing systems?
			How many installations have they done in your area?
			Are they properly licensed and certified?
			What warranties do they provide?
			How will routine maintenance and repairs be handled?
E. Estimate the costs of your project.
	Additional Project Costs:					Ongoing Operating Costs:
			Installation (labor)					Routine maintenance
			Permits					Repairs not covered by warranty
			Support structure(s)					Liability insurance
			Protective equipment required to interconnect with the utility company's system					Property taxes (check with your taxing authority to see if exemptions are available)
			Wiring
			Metering
			Inverter
			Batteries and other options
			Sales tax
			Extended warranties
F. Determine if you want to operate in parallel with the utility system.
	You can choose to operate your generator either as a stand-alone system or in parallel with the utility company.
			A stand-alone system requires a double-throw transfer switch that isolates your generator from the utility company’s system. The transfer switch ensures that you are receiving power only from your generator or only from the utility, not both at the same time. Power from your generator would not backfeed into the utility company’s system.    Since PV or wind systems generate electricity intermittently (and not necessarily at the same times you want to use it), you will probably want to include a battery bank in a stand-alone system. The batteries will supply power to your home or business whenever it is needed, and will be recharged when sunlight or wind is available. Battery systems can be very expensive. PV or wind system installers can help you estimate the costs.
			If you choose parallel operation, your installation will be designed to accommodate two-way power flow. When the output of your generator exceeds what is being used in the home or business, the excess power flows back into the utility company’s system. This type of installation avoids the cost of a battery system, but involves additional costs for interconnection, as well as the cost of metering for the excess power sent back to the utility company.    If you choose parallel operation and sell excess power to the utility company, Ameren will buy it at the avoided energy rate, which is the utility’s cost of generating power. This rate is lower than the average price you pay for power from Ameren, because your total price also includes the costs of transmission and distribution systems needed to deliver the power to your home or business. Historically, the avoided energy rate has been around 1-2 cents per kWh, but check the applicable tariff for the latest avoided energy rate:
			AmerenUE: Electric Power Purchases from Qualifying Facilities (QF)
			AmerenIP: Electric Power Purchases from Qualifying Facilities (QF)
				Tariff QF
				Tariff QF Informational Filing
			AmerenCIPS: Electric Power Purchases from Qualifying Facilities (QF)
				Tariff QF
				Tariff QF Informational Filing
			AmerenCILCO: Electric Power Purchases from Qualifying Facilities (QF)
				Tariff QF
				Tariff QF Informational Filing
G. Estimate your annual savings.
			Check your electric bill to determine the price you pay per kilowatt-hour (kWh). The cost per kWh varies depending on several factors, including your level of consumption and whether you are a residential or business customer. Be sure to calculate the annual average price you pay, since summer rates are higher than winter rates.
			Estimate your savings, including both the value of the kilowatt-hours you will avoid purchasing from the utility company, as well as the value of any excess kilowatt-hours sold to the utility at the avoided energy rate.
			Example: In Missouri and Illinois, assume a PV system can generate about 1,600 kWh annually per kW of rated capacity. You and your dealer have determined that roughly 50% of your system’s output will displace power you would otherwise purchase from the utility company and the remainder will be sold to the utility company. If your annual average price is 7 cents per kWh and the avoided energy rate is 2 cents per kWh, the estimated savings for a 1 kW system would be:           Savings = 1,600 x 50% x $0.07 + 1,600 x 50% x $0.02 = $72 per year    Note:  This is only an example. Your actual savings per year may differ.
H. Decide how to finance your project.
	PV or wind systems for homes are usually financed through mortgage loans. Businesses that install PV or wind systems will use their existing capital sources, usually conventional bank loans or Small Business Administration loans.    Special incentives and tax breaks may be available to help fund your project. The following Web sites provide additional information:
			U.S. Dept. of Energy – Efficiency and Renewable Energy Network
			Illinois Renewable Energy Resources Programs
			Missouri Department of Natural Resources
I. Before purchasing or installing any equipment for parallel operation, you must contact Ameren and allow them to review the interconnection design.
	If you intend to operate your system in parallel with the Ameren system, Ameren must review your project before operation to determine whether your project could adversely affect the safety, reliability or quality of local electric utility service.    Ameren's review of your project shall not be construed as confirming or endorsing the project design or as any warranty of safety, durability or reliability of the project.    Learn more about interconnection requirements for renewable energy systems.