AD et al I think one appropriate search parameter is EROEI (Energy Return On Energy Invested).
At this site (p 21), http://www.haitiregeneration.org/sites/hri7/files/attached_files/USAID_Alternative_Cooking_Technologies_Haiti_2011.pdf I found for pellets a value of 12:1 A widely different number was given by wiki at 2% for pelletizing at http://en.wikipedia.org/wiki/Wood_pellet Probably not fair, but inverting might say EROEI is 50:1 The cite [3] was a study by a well known analytical group (Manomet) Both of these groups mentioned Biochar - so now I want to read both cites more carefully. Obviously I/we need to look harder . Hopefully others will jump in. I need to bring in Biochar - which provides carbon negativity - which doesn't fit well into EROEI dialogs. Having more energy and carbon neutrality for centuries to millennia is where I am coming from. Re ethanol, I see EROEI as around 1- 1.5:1 with corn as input, but 9:1 for sugarcane. Thanks for the question - on a very important topic. Ron ----- Original Message ----- From: "Anand Karve" <[email protected]> To: "Discussion of biomass cooking stoves" <[email protected]> Sent: Tuesday, March 13, 2012 7:09:00 PM Subject: [Stoves] Energy loss in making high grade fuels Dear Stovers, Ron Larson raised the point of energy lost while charring agricultural waste in our portable charring kilns. I have since then been thinking about loss of energy in making other types of fuels too. Take for instance ethanol. I was told that the raw product of fermentation has less than 10% ethanol, which is then repeatedly distilled to bring it to 95 (rectified spirit). This is further treated to give 100% ethanol. There is also a lot of talk about biomass pellets. Compressing light biomass into pellets or briquettes also requires a lot of energy. In the case of charring, the energy required for the process of charring is provided by the biomass itself that is being charred. By subtracting the energy of the charcoal from the energy in the original biomass, one can easily calculate the loss. But in the case of the other two examples, the energy comes from external sources and it is always treated by the processor as his best guarded secret. Can anybody throw some light on the energy loss in making alcohol and biomass briquettes? How much is the net gain in Energy in these two products? Yours A.D.Karve -- *** Dr. A.D. Karve Trustee & Founder President, Appropriate Rural Technology Institute (ARTI) _______________________________________________ Stoves mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org for more Biomass Cooking Stoves, News and Information see our web site: http://www.bioenergylists.org/
_______________________________________________ Stoves mailing list to Send a Message to the list, use the email address [email protected] to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org for more Biomass Cooking Stoves, News and Information see our web site: http://www.bioenergylists.org/
