Author ' s personal copy Energy resources and use : The present ( 2008 ) situation and possible sustainable paths to the future

Recent estimates and forecasts of the oil, gas, and coal resources and their reserve/production ratio, nuclear and renewable energy potential, and energy uses are surveyed. A brief discussion of the status and prospects of fossil, nuclear and renewable energy use, and of power generation (including hydrogen, fuel cells, micropower systems, and the futuristic concept of generating power in space for terrestrial use) is given. Ways to resolve the problem of the availability, cost, and sustainability of energy resources alongside the rapidly rising demand are discussed. The author’s view of the promising energy R&D areas, their potential, foreseen improvements and their time scale, and last year’s trends in government funding, are presented. 2009 Elsevier Ltd. All rights reserved. 1. Executive summary 1.1. The current energy resources and consumption situation has generally worsened relative to that at the end of 2006 Amajor concern (or opportunity?) is that the price of oil is lately growing very rapidly, from $28 in 2003, to $38/barrel in 2005 and occasionally to above $80 in 2006 and >$145 (so far!). This price is one to two orders of magnitude higher than the cost of extraction, possibly meaning that financial speculation is overwhelming supply and demand, and all technical improvements. In 2007world primary energy use rose by 2.4%,with the increase rate slightly dropping (Fig. 1), but likely to rise again soon, as the large developing countries in Asia keep improving their standard of living, China’s rose by 7.7% (lowest since 2002), India’s by 6.8%, US by 1.6%, Japan’s dropped by 0.9%, and EU’s dropped by 2.2%. The reserves-to-production ratio (R/P) remains rather constant: w40 for oil, w60 for gas, and 200þ for coal, and mostly rising (Figs. 2, 3)! There probably exists sufficient oil and gas for this century, and coal for 2 or more. Tar sands and oil shales are becoming more attractive and available in quantities probably exceeding those of oil and gas. Nuclear power produces w16% of world electricity; the number of reactors is increasing very slightly; public perception is improving, new government initiatives started, but the same problems remain. Renewable energy can satisfy w2 orders of magnitude more than the world energy demand, but negative impacts aren’t inconsequential. Wind and solar PV are experiencing an exponential growth as costs decrease; interest is renewed in solar-thermal power. Strong subsidies for converting food to fuel are increasingly proven to be a mistake, helping triple the price of foods and reducing their availability, and raising water consumption, all as predicted by some ahead of time. While hydrogen, and fuel cells, continue to be valuable in the energy portfolio, they have so far not met the expectations expressed by the huge R&D investments made by many governments. This could have been foreseen bymore careful early analysis, and some of the moneys and valuable scientists’ time could have been spent better. The plug-in electric or hybrid car seems to be the preferred route to private transportation. Development of traffic management, roads, and public transit are at least as important. Costing of energy resources remains inequitable, as it doesn’t include subsidies, or environmental and other consequences. Development of renewable energy, and of all energy systems for that matter, is dominated by the highly controlled, cost-unrelated, highly fluctuating and unpredictable conventional energy prices. Fuel and energy consumption in general must be significantly constrained, with due attention to prevention of the rebound effects. The ‘‘Living Planet Index’’ is estimated to have declined since 1970 by about 30%, and the ‘‘Ecological Footprint’’ increased by 70% * Tel.: þ1215 8984803; fax: þ1 215 5736334. E-mail address: [email protected]