Self-Generation Principles: Making Your Own Power/Electricity

At first glance, generating your own electricity using renewable fuel sources seems like the ideal way to avoid monthly utility bills. For some homeowners, self-generation is a choice that makes sense for their circumstances and fits into their values. However, self-generation involves investing your money and your time doing research, comparing products, and maintaining your system. Depending upon your , you might not end up saving money, but homeowners who do choose to generate clean energy like being independent and knowing that they are minimizing their impacts on the environment.

When is Self-Generation Appropriate?

Self-generation might be right for you if:

  • A grid connection is not available in your area or can be made only through an expensive line extension. (The cost of running a power line to the utility grid at a remote site can be prohibitive, ranging from $15,000 to more than $50,000 per mile, depending upon the terrain.)
  • You have an interest in gaining energy independence from your utility.
  • You would like to reduce the environmental impact of electricity production.
  • Your site has adequate renewable .
  • You have a strategy for meeting your energy needs when renewable resources aren't available.
  • Your state or utility provides for net metering, which allows you to interconnect your system with your utility and sell any excess generation to your utility.

In addition to considering the above, you should also:

  • Research potential legal and environmental obstacles.
  • Obtain cost and performance information from manufacturers.
  • If cost-effectiveness is a key consideration, perform a complete economic analysis that accounts for a multitude of factors.
  • Understand the basics of small renewable energy systems.
  • Review possibilities for combining your system with other energy sources, backups, and energy improvements.
  • Plan for ongoing system .

Analyzing Your Loads

Note: This example shows a partial load analysis. You will need to include all items that require electricity to operate.

Performing a detailed load analysis is critical to sizing your renewable energy system. A load analysis is a measure of your daily energy needs. To conduct a load analysis, list all of your daily energy loads. A load includes anything that uses electricity from your power source, such as lights, heating and air conditioning, televisions, radios, and small and major . Some loads use electricity all the time, such as refrigerators, whereas others use electricity less often, like power tools. To determine your total energy consumption, multiply the wattage of the appliance by the number of hours it is used in a day. Some appliances do not give the wattage, so you may have to calculate the wattage by multiplying the amperes times the volts.

(Information about wattage, amperage, and voltage can be found on a sticker or metal plate attached to the appliance itself or on a tag attached to the electric cord.) After adding the totals for each appliance, you can decide what power output you need for your renewable energy system.

Analyzing Your Site and Sizing Your System

Your load analysis is a key component of sizing your renewable energy system. The renewable resource available at your site is the other key component.

The Benefits of Net Metering

Net metering allows homeowners with self-generating systems to sell their excess power to the utility. Net metering can make self-generation economically attractive to you, depending on how it is implemented in your state. The best situation is when your meter turns backward and generation is fed into the utility grid. This essentially allows you to bank your generation until you need it. You are selling your excess power to the utility at the same rate you pay for electricity, called the retail rate. In some states, a less attractive option is available, in which you sell your generation to the utility at the utility's avoided cost. This is the cost the utility would have to pay to purchase electricity on the wholesale market. The utility's avoided cost can be as much as ten cents per kWh less than the retail rate. Your utility will specify the interconnection requirements for net metering. Check with your utility before planning to take advantage of net metering.