5.4.1 Upstream Factors: Biomass Collection and Delivery

The “billion ton vision” is a program to access a billion tons of dry biomass per year to produce bioethanol (and other biofuels) to replace 30% of U. S. gasoline consump­tion by 2030.69 One of the key parameters in a large-scale restructuring of the U. S. national fuel industry is that of supplying biomass raw material at such a high rate and at an economically acceptable cost.

The logistics and transportation costs of such large amounts of low-value, high- volume raw materials have only recently attracted serious consideration. Canadian studies comprise the most detailed considerations of these highly practical ques­tions now that cellulosic ethanol facilities are nearing industrial reality. For an agri­cultural economy (and climate) like Canada’s, wood is highly likely to be a large fraction of the biomass supply, initially from forest harvest residues and “energy plantations” on marginal farmland.70 For wood chips, larger production plants (up to 38 million dry tons of biomass/year) are more economic than smaller units (2 million tons), and truck delivery is limited to such small units by issues of traf­fic congestion and community acceptance.71 Combined road and rail shipping, that is, initial collection by truck followed by trans-shipping to rail, is only economic when the cost per unit distance of the rail sector is less than the trucking-only mode because of the incremental fixed costs: for woody material, the minimum economic rail shipping distance is 125 km (78 miles), whereas for cereal straw, the minimum distance extends to 175 km (109 miles).72 Existing rail networks impose, however, a serious restriction (that of their location), supplying only sites close to already positioned track; road transport is more versatile. Factoring in additional consid­erations, including air emissions during transport, definitely favors rail transport.73 Policy changes and new infrastructure investment appear therefore to be inevitable if the development of bioethanol production is not to be inhibited by objections of cost and pollution.

Focusing on corn stover and wheat straw as raw material inputs, a study of North Carolina concluded that more than 80% of these resources were located in the coastal area; four ethanol plants with feedstocks demands of between 146,000 and 234,000 dry tons/year required collection radiuses between 42 and 67 km (26-42 miles).74

The siting of production facilities to minimize transportation costs implies a contradiction with the economies of scale possible with larger production units. This is made more likely if relatively marginal biomass inputs such as municipal solid waste are to be considered.75 Urban fringes might be close to existing landfill sites and also within short distances of field crop residues, wastes from horticultural industries, and seasonal supplies of tree and plant residues from urban parkland. As discussed previously (section 5.3.2), the ability to design and build smaller-scale bioethanol production units, especially if they can utilize a variable and adventitious supply of feedstocks, would be highly beneficial to match the fragmented nature of the cheapest likely raw materials.