Net metering

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Net metering is a state level electricity policy for consumers who own "qualifying facilities," which are generally smaller, renewable energy sources such as a wind or solar power. "Net", in this context, is used in the sense of meaning "what remains after deductions" -- in this case, the deduction of any energy outflows from metered energy inflows. Under net metering, a system owner receives retail credit for at least a portion of the electricity they generate. The ideal has your existing electricity meter spinning backwards, effectively banking excess electricity production for future credit. In reality, the rules vary significantly by country and possibly state/province if net metering is available, if and how long you can keep your banked credits, how much the credits are worth (retail/wholesale), etc. In North America, 40 U.S. states have some form of net metering in place, and some Canadian provinces have net metering programs. The United Kingdom government is reluctant to introduce the net metering principle because of complications in paying and refunding the value added tax that is payable on electricity, but pilot projects are underway in some areas.

Germany, on the other hand, has adopted an extreme form of net metering, whereby customers get paid for any electricity they generate from renewable energy on their premises. The actual electricity being generated is counted on a separate meter, not just the surplus they feed back to the grid. For the solar power generated, roughly 2 times the retail rate per kWh for residential customers is being paid in order to boost solar power (figure from 2006). Wind energy, in contrast, only receives around a third of the retail rate because the German system sensibly pays only what each source actually costs.

1 Time of use net metering
2 Market rate net metering
3 Net purchase and sale
4 See also
5 References
6 External links

[edit] Time of use net metering

Time of use net metering employs a specialized reversible meter that is programmed to value electricity at fixed values during different periods of the day, which may also vary with differing seasons. This is available in California and is highly favorable to smaller systems that displace the highest cost electricity and systems where the user's demand load may be managed so that there is a net production of electricity during high cost periods. This can be done for example, by chilling water during off peak times for air conditioning use during high demand periods, or by pre-cooling the thermal mass of the building during low cost periods.

In North Carolina initial net metering rules were put in place in 2005 to prohibit systems that include backup battery power, however due to consumer feedback this restriction was lifted in July 2006.

Net Metering is generally a consumer-based renewable energy incentive. While it is important to have Net Metering available for any consumer that interconnects their renewable generator to the grid, this form of renewable incentive places the burdens of pioneering renewable energy primarily upon fragmented consumers. Often over-burdened energy agencies are not providing incentives on a consistent basis and it is difficult for individuals to negotiate with large institutions to recover their Net Metering credits and/or rebates for using renewable energy.

In Kansas they do not have a consumer Net Metering incentive, but they have a renewable metering incentive on the wholesale level that provides the wholesale commerce of renewable energy at 150% the avoided cost. Thus, the incentive one receives in this case is dependent not upon the price of retail electricity per kWh, but upon the price of wholesale electricity.

The Kansas Solar Electric Co~operatives [K-SEC] was founded January 2005 by Eileen M. Smith, M.Arch. VITAE as a non-profit and non-competitive renewable electricity cooperative. K-SEC Phase I Demonstration is structured around Kansas House Bill 2018 passed in 2003 by Kansas Representative Tom Sloan. See Kansas Statutes Annotated Chapter 17-4661 and 17-4655

The K-SEC program has the goal of installing 1,000 MWp building-integrated photo voltaic [BI-PV] solar electricity by 2018. This translates to approximately one hundred million SF of BI-PV solar roofing or one million SF BI-PV roofing in 100 of the 105 counties of Kansas. This will require 70,000 to 100,000 SF BI-PV per county per year for ten years. K-SEC will not sell the solar systems, but they are going to lease consumer rooftops in exchange for a high-tech battery back-up system for fifty years. K-SEC will manufacture, install, monitor, maintain and sell the electricity wholesale. K-SEC will provide numerous job opportunities to rural and urban Kansas communities from manufacturing to solar system design, installation, maintenance, monitoring and electricity sells.

The foundational structure for the K-SEC Program is the Kansas Solar Electric Buildings Registry and GIS Database. A list is being compiled of Kansas homes and buildings that have unshaded roofing surface that could accommodate 100 SF to 50,000 SF of BI-PV solar materials. The rooftops must have south to southwest facing or flat rooftops.

The K-SEC Program is important for Kansas where 72.5% of the electricity Kansas presently consumes is generated by coal-fired power plants. In 2004 and 2005 projects totaling a 55% increase in coal-fired power plants were proposed in Kansas. Kansas Department of Health and Environment has already issued warnings not to eat the fish in Kansas rivers and lakes due to the extreme amount of toxic mercury from coal-fired power plant emissions. Coal-mercury toxins cause a variety of health hazards with the most serious being fetal damage and mental retardation in children. Mercury and CO₂ emissions are major cancer-causing toxins.

[edit] Market rate net metering

In market rate net metering systems the user's energy use is priced dynamically according to some function of wholesale electric prices. The users' meters are programmed remotely to calculate the value and are read remotely. Net metering applies such variable pricing to excess power produced by a qualifying systems. Market rate metering systems will be implemented in California starting in 2006 and under the terms of California's net metering rules will be applicable to qualifying photovoltaic and wind systems.

[edit] Net purchase and sale

Net purchase and sale is a different method of providing power to the electricity grid that does not offer the price symmetry of net metering, making this system a lot less profitable for home users of small renewable energy systems.

Under this arrangement, two uni-directional meters are installed—one records electricity drawn from the grid, and the other records excess electricity generated and fed back into the grid. The user pays retail rate for the electricity they use, and the power provider purchases their excess generation at its avoided cost (wholesale rate). There may be a significant difference between the retail rate the user pays and the power provider's avoided cost.^[1]

[edit] See also

[edit] References

^ U.S. Department of Energy EERE Consumer's Guide: Metering and Rate Arrangements for Grid-Connected Systems, updated September 12 2005, accessed 23 January 2006