Combined Heat & Power

The Convergence of Microprocessors, Sensors, Communications & CHP
Distributed Solutions for Distributed Problems

Vision:

To create a comprehensive systems view of grass in applications ranging from Heat, Power, Nutrient Management, Open Fields & Landscape Preservation, as well as a sustainable, integrated, grass and wood bio-energy strategy that promotes energy independence and security.

Problem Statement:

Fossil fuel prices are being driven upwards by a growing divergence between demand and supply, possibly complicated by “Peak Oil”;

The U.S. can no longer afford the luxury of fossil fuels that have a negative net energy return on total energy inputs required for their production;

Reliance on insecure and vulnerable foreign fossil fuel supplies constrains U.S. foreign policy options and exposes the U.S. economy to risky disruptions and distortions;

Burning fossil fuels releases sequestered carbon into an already overburdened atmosphere;

Centralized generating plants create single points of failure - a Homeland Security issue;

The U.S. economy can no longer afford power plants operating below 67% efficiency - 49% of US electricity is made by burning coal at less than 35% efficiency;

If you would like a PDF file of the current draft of the 40 page the working paper "A Scenario for Grass in New England", please send me a note asking for it. This paper has lead to the formation of the New England Grass Pellet Collaborative, Inc., a new non profit corporation registered in the state of Vermont. The Collaborative will be sponsoring the Green Valley Grass Pellet Project of 2006. Shelburne Farms will be an active participant and has graciously agreed to host the project.

Net Energy Realized:

A key metric for biofuels is the net energy gain they represent after allowing for all of the energy inputs required to produce them. Grass appears to offer the best return on energy invested to produce it: 12:1 according to R.E.A.P. Canada. Biodiesel has been rated as high 3.2:1 but is now generally rated closer to 2:1 . On the other hand, ethanol made from corn in North America, according to the Wikipedia (Minnesota Department of Agriculture), offers 1.34:1 return on the energy investment. This raises a question as to why research on ethanol from corn is currently receiving the lion’s share of U.S. Government research dollars for dedicated energy crops. One possibility is that a premium is associated with a liquid bio-fuel.

It is suggested that Net Energy must be balanced with the Application Value of the biofuel produced. It should be further noted that agricultural subsidies have distorted the choice of input stocks for making biofuels. Research may well identify a bioethanol feed stock with a much better net energy value than corn. Soybeans may not, in fact, be the optimal input stock for biodiesel. Industrial hemp, for example, might be a much better biofuel feed stock. There is evidence that Switch grass is superior to corn as a feed stock for bioethanol.

According to R.E.A.P., “Switchgrass has a net gain of about 11 barrels of oil energy equivalent per acre. This compares favourably to other commercial biofuel alternatives. Corn ethanol, for example, only produces enough net energy on one acre to replace 1.5 barrels of oil. Corn also requires moderate to high quality farmland for its production; switch grass can be grown on lower quality lands.”

By way of comparison, gasoline made from fossil oil is reported to have a net energy value of only .85:1. This shows that the return on the investment of the total energy inputs required to deliver gasoline to the retail pump is negative.

Posted by Jock Gill at December 23, 2005 9:53 AM | TrackBack