Wood resource

Wood is a renewable energy resource only if it is grown as fast as it is consumed. Moreover there are ecological imperatives for the preservation of natural woodland and forests. The world's wood resource is consumed not just for firewood, but for sawn timber, paper making and other industrial uses. In addition, much forest is cleared for agriculture with its timber just burnt as 'waste'. Approximate estimates of present and potential biomass energy resources are given in Table 11.3, including forests and woodland, but the accuracy in most countries is no better than a factor of two, partly because of different definitions of exactly what are 'forests' and 'woodlands'.

In many countries, firewood consumption exceeds replacement growth, so that fuelwood is a depleting resource. In India, for example, present consumption of fuelwood is estimated to be around 200 Mty-1, of which only about 20Mty-1 constitutes sustainable availability from forests. About 100 Mty-1 is derived from non-forest sources such as from village woodlots, trees or shrubs on the edge of fields and roads, etc. The balance represents non-sustainable extraction from forests plus miscellaneous gathering of woody material. Moreover, the populations of firewood-using countries are increasing at 2-3% per year, thus tending to increase the demand for cheap cooking fuels. Fuelwood collection for household consumption, usually a task for women and children, is becoming more burdensome as fuelwood becomes scarcer. The proportion of rural women affected by fuelwood scarcity is around 60% in Africa, 80% in Asia and 40% in Latin America. Moreover, gathering firewood may require 1-5 hours per day. Alleviating these difficulties requires both intensive reforestation and a switch to more efficient cooking methods.

Regeneration may occur in natural forest or in man-made plantations (which usually grow faster and are to be encouraged). Plantations grown especially for energy supply need different management (silviculture) techniques than plantations grown primarily for timber (Sims 2002). Combustible wood need not be grown in long straight lengths, and can therefore be harvested much more often (at 3-5 years rather than ~30 years). Coppicing (i.e. leaving the roots in the ground and cropping only the branches) is successful with many tree species; it reduces (costly) labour for planting and weeding, and also reduces soil erosion compared with repeated replanting.

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Getting Started With Solar

Getting Started With Solar

Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.

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