Let's face it -- Most Environmental Groups only begrudgingly accept biomass energy as truly green. In their view, energy options such as wind or solar are much "Greener". After all, although bio-energy can claim the "Carbon Neutral Argument", it still emits air pollutants such as greenhouse gas emissions, where solar and wind do not.
The fatal flaw in these Environmental Group's perspective is their failure to understand basic Energy 101 involving electricity generation -- and how an integrated electricity grid works.
In these Environmental Group's perception of the World, green technology generating options are viewed on a stand-alone Micro Basis. For example, solar and wind options emit no greenhouse gas emissions, where biomass energy does.
In reality, electricity generation options work on a Macro Basis of the integrated resource grid that includes all forms of energy -- both renewable and fossil fuel generation options.
In determining the value of renewable energy sources, a key question must always be: What does a specific technology option displace on the integrated grid?
To answer this question, one must understand "basic terms" of (1) base load, (2) intermediate load, and (3) peaking load generating options.
Because of availability (number of hours and when the sun shines or the wind blows), solar and wind options are typically considered either intermediate or peaking technologies on an integrated resource grid. As such, wind and solar options will displace primarily natural gas generating units (where natural gas is by far the cleanest of fossil fuels compared to coal and oil).
Conversely, biomass energy and geothermal options are typically considered base load, and would primarily displace in much of the U.S., coal fired generation.
Why is understanding things like base load versus intermediate or peaking load important? Well, according to the U.S. Department of Energy, base load coal fired electricity generation produces approximately 90% of all CO2 emissions from electricity generation.
Two good Web resources to understand these concepts can be found at:
(1) The Common Purpose Institute's webpage on Biomass Energy Quick Facts and
(2) Renewable Energy World's discussion of the Integrated Resource Grid