IWMI confirms small potential for first generation biofuels in China and India due to water issues

A very basic scenario analysis by Sri Lanka's International Water Management Institute (IWMI) indicates that first generation biofuels made from crops like corn or sugarcane will add to the strain on already stressed water resources in China and India. The IWMI recommends the use of water-efficient crops instead and urges analysts to take water needs of bioenergy production more stringently into account.

The findings are a bit outdated because the Chinese government earlier already decided that it would only utilize water efficient crops like sweet sorghum, grasses, desert pine and cellulosic biomass (previous post and here). These resources are not analysed in the report, prompting a critical reaction by a Chinese bioenergy official.

Global bioenergy potential by 2050, different scenarios. Note China and India's relatively small capacity. Source: IEA Bioenergy Task 40.

Still, IWMI's research confirms data from many earlier projections. The International Energy Agency's Bioenergy Task 40, which has been making the most thorough global assesments of the biofuels potential, found that both China and India's carrying capacity is small, compared to that of other regions. This doesn't come as a surprise given the countries' large populations and limited per capita land resources. In a latest set of projections (Smeets et al., February 2007), scientists of Task 40 found that East Asia's sustainable biofuels potential is between 22 and 194 Exajoules by 2050; that of South Asia only between 22 and 37 Ej (earlier post; map, click to enlarge). Compare this to Africa's (317Ej max) or Latin America's (221Ej max).

IWMI’s research under the 'Comprehensive Assessment of Water Mangement in Agriculture' model shows that at a global average, the biomass needed to produce one litre of biofuel from such crops like maize and sugarcane evaporates between 1000 and 3,500 liters of water, under prevailing first-generation conversion techniques (note that meanwhile, the era of fourth generation techniques drawing on engineered crops has arrived).

IWMI uses the WATERSIM model consisting of two integrated hydrological and economic modules to support its analysis. Using this model it found [*.pdf]that in India more than 60% of the cereals are irrigated. In China, more than 70%. Almost all Indian sugarcane - the crop that India uses to produce ethanol - and about 45% of Chinese maize – China’s main biofuel crop - is irrigated.

Both countries, responding to severe water shortages, initiated large projects to transfer water from water abundant to water short areas. These projects are controversial because of their costs, environmental impacts, and number of displaced people by big dams.

China
Irrigation plays a dominant role in China’s food production. An estimated 75% of total grain production, 90% of vegetables and 80% of cotton comes from irrigated areas:
energy :: sustainability :: ethanol :: biodiesel ::biomass :: bioenergy :: biofuels :: water :: irrigation :: India :: China ::

About 70% of total wheat and 60% of total maize are harvested in the Northern region (i.e. the Yellow, Huaihe and Haihe river basins), where more than 60% of the area is irrigated and groundwater resources are already extensively overexploited.

The South imports food from the water stressed Northern region and the international food market. Earlier the water rich South produced a surplus that was exported to the Northern provinces. But with economic development and associated higher opportunity costs for land and labor, agricultural production in the developed South is becoming less attractive to farmers who have more opportunities to work in non-agricultural sectors.

The total volume of water resources in China ranks sixth worldwide, but per capita supplies are only 2200 m3 in 2000, about 1/4 of the world average. Particularly, in the North -Haihe, Huaihe and Yellow river basins- per capita water resources are low, only 290 m3, 478 m3 and 633 m3, respectively and declining groundwater tables due to overdraft are common. Frequent droughts, floods and water logging hazards result in unstable agricultural production and a serious imbalance between water supply and demand). A major water transfer project from South to North currently under implementation will alleviate some of the water shortage problems, but most of the transferred water will be used in the domestic and industrial sector rather than agriculture.

Because of water limitations in the North and land constraints and high opportunity costs to labor in the South, our base scenario foresees limited scope for further improvements in production. The scenario puts a limit on land and water use to prevent further environmental degradation. Maize demand in China will increase substantially to 195 million tons in 2030 (up by 70% from 2000), mainly because of growth in per capita meat consumption as a result of income growth.

Part of the additional demand can be met through productivity growth and slight area increase, but even under optimistic yield growth assumptions imports must increase to 20 million tons from 2 million tons in 2004. Under such a scenario it is quite unlikely that the additional maize demand for biofuel can be met without further degrading water resources or major shifts of cropping pattern at the expense of other crops. More likely, under an aggressive biofuel program China will have to import more maize (or the crop displaced by maize), which will undermine one of its primary objectives, i.e. curbing import dependency.


India
Irrigation plays a major role in India’s food supply. At present some 63% of the cereal production originates from irrigated areas. Wheat and rice are mostly produced under irrigated conditions while maize and other grains are grown in rainfed areas. Close to 85% of the area under sugarcane -the crop currently most used in bioethanol- is irrigated. It is estimated that the total harvested area amounts to 175 million hectares (in 2005) of which roughly 45% is irrigated. More than half of the irrigated area is under groundwater irrigation, mostly privately owned tubewells.

Total renewable water resources are estimated at 1887 km3, but only half (or 975 km3) is potentially utilizable. Total water resources amount to 2025 m3 per capita (for the year 2000), or only around 1100 m3 of potentially utilizable per capita supplies. Water withdrawals in India were estimated at 630 km3 in the year 2000, of which more than 90% was for irrigation. Spatial variation is enormous. The river basins of the Indus, Pennar, Luni and westerly flowing rivers in Kutsch and Gujarat are absolute water scarce, and much of North India suffers from groundwater overdraft.

To address water scarcity, the government of India is exploring the possible implementation of a series of large scale interbasin transfers to bring water from water abundant to water short areas. This so-called “Linking of Rivers” project is controversial, because it is expensive; it will have adverse impacts on biodiversity and freshwater ecosystems, and will cause the displacement of millions of people. Though parts are under development now, it is unlikely that this project will be fully implemented and operational in the near future. Our base scenario therefore foresees relatively limited scope for further irrigation development. The scenario adopts optimistic assumptions to improve productivity in both irrigated and rainfed agriculture.

Cereal and vegetable demand in India is projected to increase by 60% and 110% respectively from 2000 to 2030. The irrigated harvested area is expected to slightly increase from 75 to 84 million hectares. A major part of these increases will be met through improvements in yields though small increases of imports are inevitable. Sugarcane production increases from 300 to 605 million tons for food purposes. Our biofuels scenario implies that for the production of bioethanol an additional 100 million tons of sugarcane is needed, for which 30 km3 additional irrigation water needs to be withdrawn. This amount will likely come at the expense of the environment or other irrigated crops (cereals and vegetables), which then need to be imported. For many years, the Indian government has focused on achieving national food self-sufficiency in staples.

More recently, as the imminent danger of famines has decreased and non-agricultural sectors have expanded, the national perspective regarding production and trade has changed. But it is unclear if India would choose to import food to free up necessary resources to grow biofuel crops, the report says.


In its discussion of the findings the report concludes that:

If all national policies and plans on biofuels are successfully implemented, 30 million additional hectares of crop land will be needed along with 180 km3 of additional irrigation water withdrawals. Although globally this is less than a few percentage points of the total area and water use, the impacts for some individual countries could be highly significant, including China and India, with significant implications for water resources and with feedback into global grain markets. In fact it is unlikely that fast growing economies such as China and India will be able to meet future food, feed and biofuel demand without substantially aggravating already existing water scarcity problems, or importing grain, an outcome which counters some of the primary reasons for producing biofuels in the first place.

Unless other less water intensive alternatives are considered, biofuels based on such first generation techniques and crops are not environmentally sustainable in China and India.

This analysis assumes no major changes in feedstock. Yet, this may become an important factor in the biofuel discussion. From a water perspective it makes a large difference whether biofuel is derived from fully irrigated sugarcane grown in semi-arid areas or rainfed maize grown in water abundant regions. The use of water-extensive oilseeds (such as Jatropha trees), bushes, wood chips and crop residuals (i.e. straw, leaves and woody biomass) is promising in this respect, though a few caveats are necessary.

The IWMI concludes that biofuel policies should put green energy into a blue context and take water issues into account.

A US study on water withdrawals for corn published recently by the National Research Council similarly concluded that the significant acceleration of first-generation biofuels production could cause greater water quantity problems depending on where the crops are grown.

If the use of corn for ethanol production increases further it may harm water quality could be considerable, the report concluded (previous post).

References:
Charlotte de Fraiture Mark Giordano Liao Yongsong, Biofuels and implications for agricultural water use: blue impacts of green energy [*.pdf], International Water Management Institute, Sri Lanka - October 2007.

Edward M.W. Smeets, André P.C. Faaij, Iris M. Lewandowski and Wim C. Turkenburg, "A bottom-up assessment and review of global bio-energy potentials to 2050", Progress in Energy and Combustion Science, Volume 33, Issue 1, February 2007, Pages 56-106, doi:10.1016/j.pecs.2006.08.001

Energy Current: China: Biofuel will not hit food, water supply - October 12, 2007.

Biopact: Report: increase in corn ethanol production could significantly impact water quality and availability in the United States - October 10, 2007

Biopact: A quick look at 'fourth generation' biofuels - October 08, 2007

Biopact: China unveils $265 billion renewable energy plan, aims for 15% renewables by 2020 - September 06, 2007

Biopact: China to boost forest-based bioenergy, helps win battle against desertification - July 17, 2007

Biopact: China mulls switch to non-food crops for ethanol - June 11, 2007