Solar Installation Questions and Answers

The best way to determine if adding distributed generation (Solar) to your home is to educate yourself prior to making a decision. As you read these Q/As, ask yourself what your primary reason for the addition of solar panels. Do you primarily want to save money on your energy costs; provide electricity to your home during a power outage; or are there other reasons? Keeping your primary reason in mind will help you determine if this is a good investment for you.

What is distributed generation (DG)?

Distributed generation is any electricity generating technology installed by a customer or independent electricity producer that connects to the distribution system level of the electric grid. Customer owned roof top solar generation is an example of this.

How do I know if my system is distributed generation?

If you are a customer installing equipment to generate electricity at your home, business, or other privately owned property, you are installing distributed generation. If you plan to connect this system to the electric grid, you will need to follow the utility's interconnection process.

Does the electric company pay you for solar energy?

If you generate more power than you use from the electric company in a given month, you will see a credit applied to your bill.

During a utility power outage, will my solar panels still provide electricity?

No, unless you have a battery backup system for storage or a generator, when the grid goes down, your power will be off.

Does SWEPCO maintain my solar panels, i.e. clean them and clear the ice/snow?

No, the customer is responsible for all maintenance of their distributive generation system (Solar Panel system).

What is the typical wattage of a residential solar panel?

Sizes vary and the typical size is 320 watts.

How much does a residential solar panel weigh?

A typical solar panel weighs approximately 40 pounds; therefore, you should make sure that your roof could sustain the total weight of the solar panels you are considering installing on your roof. Twenty panels will weigh approximately 800 lbs.

What is the size of a residential type solar panel?

A single solar panel is typically 3.25 feet by 5.4 feet. If you are considering a roof installation, you will be limited by the total available roof area. Twenty panels would require about 400 sq. ft. of space.

Should I install solar panels over the entire area of my roof?

There are many factors to consider. Shade from nearby trees and optimum exposure to sunlight will influence your systems solar production. Most installations are typically on southerly exposed roofs.

What does invertor size have to do with the solar panels?

If you install 20 solar panels, one would assume that your system would produce approximately 6,400 watts (6.4 kW), but that is limited by the inverter size. If the invertor is only 5 kW, and you install solar panels that total greater than 5 kW, you will only produce a maximum of 5 kW.

How much will I save by installing rooftop solar?

Many factors can affect your end savings, including the amount of energy produced from solar panels; the timing of your solar production and your actual energy use and requirements; the weather and obviously the cost of the system. In our region of the country, the average maximum kWh production from 1 kW of total installed solar panels (approximately 3 panels) would equal approximately 130 kWh per month. If you installed 30 panels, (approximately a 10 kW system) that would be a maximum of about 1,300 kWh per month. You would need to factor in the cost of the system and weigh that against the potential savings. The primary benefit from your energy production is the reduction in energy you need to purchase from the utility’s grid, not the revenue from excess energy sent back to the grid.

How does the billing work?

Arkansas

In SWEPCO Arkansas service territory, the Net-Metering Customer is billed on a monthly basis the charges applicable under the currently effective standard rate schedule and any appropriate rider schedules. Under Net-Metering, only the kilowatt-hour (kWh) units of a Net–Metering Customer’s bill are netted. If the kWhs supplied by the Electric Utility exceeds the kWhs generated by the Net-Metering Facility and fed back to the Electric Utility during the Billing Period, the Net-Metering Customer is billed for the net billable kWhs supplied by the Electric Utility in accordance with the rates and charges under the Net-Metering Customer’s standard rate schedule. For Example, in one month, if you use 100 kWh from your electric company and you generate 50 kWh with your solar panels, you will be billed for 50 kWh plus all applicable taxes and fees. However, if the next month, you use the same 100 kWh but you generate 150 kWh, you will not be charged for any kWh and will receive 50kWh credits toward your next month’s billing.

Louisiana

In SWEPCO Louisiana service territory, the SWEPCO Distributed Generation tariff credits the customer at the avoided cost of energy rate for all kWh sent back to the grid. The avoided cost of energy rate is adjusted each month, and historically has ranged from about $0.02 to $0.03 per kWh. For Example: During the billing month, assume a customer receives 1,000 kWhs from SWEPCO, and sends 600 kWhs back. The 1,000 kWhs would be billed at approximately 11 cents/kWh (this 11 cents/kWh includes all customer charges), and the 600 kWhs would be purchased at the Avoided Cost rate of approximately 2 ½ cents per kWh. So the initial bill would be about $110 (1,000 kWhs X 0.11), with a credit of approximately $15.00 for the kWhs returned to the grid, calculated using 2 ½ cents for the Avoided Cost rate, (600 kWhs X 0.025). In this example, the final bill would be about $95.00.

*In Louisiana, there is no additional monthly meter charge.

Texas

In SWEPCO Texas service territory, the SWEPCO Distributed Generation tariff credits the customer at the avoided cost of energy rate for all kWh sent back to the grid. The avoided cost of energy rate is adjusted each month, and historically has ranged from about $0.02 to $0.03 per kWh. For Example: During the billing month, assume a customer receives 1,000 kWhs from SWEPCO, and sends 600 kWhs back. The 1,000 kWhs would be billed at approximately 11 cents/kWh (this 11 cents/kWh includes all customer charges*), and the 600 kWhs would be purchased at the Avoided Cost rate of approximately 2 ½ cents per kWh. So the initial bill would be about $110 (1,000 kWhs X 0.11), with a credit of approximately $15.00 for the kWhs returned to the grid, calculated using 2 ½ cents for the Avoided Cost rate, (600 kWhs X 0.025). In this example, the final bill would be about $95.00.

*In Texas, the DG tariff includes an additional ‘Customer Charge’ of $8/month. This is in addition to the existing $8/month charge for each DG account.

What factors can reduce the efficiency, production ability, and savings I can achieve from my solar generator system?
  • The solar panels will be most efficient if kept clean, free of dirt, pollen, mold, and mildew build-up.
  • Shade from trees will reduce the amount of production.
  • Cloudy days will reduce the amount of production.
  • Extreme heat and extreme cold will reduce the amount of production.
  • Micro-inverters and centrally installed inverters can and do fail and if not replaced will reduce the amount of energy production. Solar panels may have a life of expectancy of 20 – 30 years, but inverters typically do not, and when they fail will require replacement to continue production.
Additional questions that to consider in the decision to add Distributive Generation:
  • How long do you plan to live in the home?
  • Is the roof structure capable of sustaining the added weight from the solar panels?
  • When the roof eventually needs repaired or replaced, what is the cost of removal and reinstallation of the solar panels?
  • Does the warranty cover all maintenance costs? What is the expected maintenance cost after the warranty expires?
  • Cost of finance charges and fees associated with the lease or loans linked to the project?
  • What is the expected life of the Solar panels?
  • What is the expected life of the invertor?