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Renewable Electricity: From Windmill to Socket

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Do your friends and neighbors tell you that they get “green” power for their home, leaving you wondering: “How can the juice coming from their outlets really be different from my electricity?” Read on to find whether that’s the case and how green power really works!

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Tracking Wind Farms

I Stock 000007240848 Extra SmallEvery time a wind turbine or other renewable power plant produces a unit of electricity, a designated registry records the time and characteristic of the event with a unique identifier. That recording creates what is called a Renewable Energy Certificate or REC. The electricity from the windmill is sent into the power grid and like water in a stream the renewable source gets mixed with other forms of electricity and the source soon becomes untraceable. This means that you were correct if you thought that your power was in fact indistinguishable from that of your green power powered neighbor. But if your neighbor’s electricity is in fact from a mix of different energy sources, where does the green claim come from?

How Do You Like Your Renewable Power?

The green’ness in your neighbor’s power comes from the fact that enough Renewable Energy Certificates are created, tagged, purchased, and retired on their behalf to match their home’s energy consumption. Renewable electricity is in fact more valuable than conventional power, and that extra value is captured in the Renewable Energy Certificate. RECs can be bought together or “bundled” with the electricity they was originally associated with or independently, “unbundled”, from it. The bundled vs. unbundled distinction creates several options for homeowners. In States with competitive power markets, green power is most often advertised as a single product combining electricity and the renewable certificates. However, the simplest way to green up your power is to stay with your local utility and purchase a quantity of RECs to match your consumption, something now available through the ClearlyEnergy platform. Based on the home’s estimated consumption, the cost to Green’Up is calculated, and can be as low as $5/month. For commercial customers, going green can be a bargain, and each case is best handled on individual basis.

No Double Counting Please!

In practice, greenin’up means that in the registry tracking the RECs, a number of certificates equivalent to your consumption are tagged as used and retired. RECs that come with the Green-E certification standard have added guarantees that the REC is indeed new, from the stated renewable source and never used before.

RECs and Solar RECs

Homes with photovoltaic panels become mini-generating stations of their own and those REC’s are tracked as well. Solar sourced REC’s are called … drumroll, SREC’s for Solar Renewable Energy Certificates and often have substantially more value than REC’s from wind, biomass or other renewable sources, but that extra value varies wildly from State to State. For homeowners in Massachusetts, DC or New Jersey, the SRECs represent a significant source of income to the solar system owners.

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