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  Methane Digester are true offsets

   METHODOLOGY FOR FORECASTING
  LONG-TERM REC GENERATION AND CO2 AVOIDANCE IMPACTS

  GRID CONNECTED FARM METHANE PROJECTS

  We help build manure digesters on farms whose baseline practice is to store their manure in storage ponds, where it is kept pending bi-annual or tri-annual spreading on the fields.  In these storage ponds, all but the very surface of the manure has no access to oxygen, so bacteria that thrive without oxygen decompose the manure, giving off gases including methane (CH4) as a byproduct, which bubble up and enter the atmosphere.  There, methane has 21 times the global warming impact of carbon dioxide.  Each 95¼ pounds of methane can be expressed as one ton of CO2-equivalent, or CO2e.

  The farms we work with install anaerobic digester systems in place of the storage ponds.  These are heated, airtight systems that accelerate the decomposition and capture the methane, which the farms then burn to generate electricity and useful heat.  The digested manure is then pumped from the digester to pre-spread storage lagoons, with virtually no future methane off-gassing.  As the CO2 emissions from burning the methane for electricity and heat are equivalent to the CO2 that would have been emitted if the manure was put directly onto the fields, the electricity and thermal energy are considered CO2-neutral.  As a result, the farms create three sources of CO2 or CO2 reductions:

      * Reductions from the displacement of electricity from fossil fuels that results from the farms' generation of electricity and delivery of that electricity to the grid ("Electricity-Based CO2 Reductions");
      * Reductions from the displacement of the farms' use of fossil fuels for heating and cooling needs that results from the farms' capture and use of heat given off by the generators ("Avoided Fossil Fuel CO2 Reductions"); and
      * Reductions from the avoidance, or abatement, of fugitive methane emissions that would have resulted from the farms' continued pond storage of manure that would have occurred in the absence of the digester ("Methane Abatement CO2e Reductions")
  On Many offset critics appear to be shadowboxing posted 2 years, 4 months ago 76 Responses