n water or water treatment and supply. There are strong energy implications in terms of transporting and treating water for consumption, especially in the context of rapid urbanization. Increasing population in cities means increasing demand for water supply and for wastewater treatment. This means increasing energy demand. The two are closely linked.
CWR: The government will soon announce its 12th 5-year plan. What are the water targets contained therein?
CWT: The Chinese government will announce its 12th Five Year Plan in March 2011. To date the CPC Central Committee has issued a proposal on formulating the plan, which contains guidance, but no specific targets. Those will most likely not be announced until March. However, we have indications on the policy direction.
China sets water targets every five years in the same way that it sets energy intensity targets. The 11th Five Year Plan (2006-2010) set binding targets to reduce water consumption per unit of industrial added value1 by 30 percent and to reduce water pollutant discharge measured as “COD” (Chemical Oxygen Demand) by 10 percent. In addition, China set an indicative target to increase irrigation efficiency. For the coming 12th Five Year Plan, a new indicator, a load limit for ammonia nitrogen, will be added as a mandatory water quality target.
Under the framework of the national Five Year Plan, each ministry will develop a sectoral plan with detailed goals and supporting actions. Regarding water resources, the Ministry of Water Resources (MWR), together with the National Development and Reform Commission (NDRC) and the Ministry of Housing and Urban-Rural Development (mohurd), are currently working on the 12th Five Year Plan for Building a Water Saving Society. Major water-dependent industries, including thermoelectric, petrochemical, and iron and steel, will be required to achieve higher water efficiency levels. We do not know yet what the targets will be, but in the previous plan, the power sector was required to improve water efficiency by 10 percent.
CWR: What are the implications for energy consumption of these targets?
PZJ: There are two different implications – one to save energy, other to use energy. With the target to control discharge of pollution we need energy to build and operate waste treatment – these are both energy consuming. So to reach water targets, we need to consume energy and this increases energy demand.
On the other hand, if we can use recycled water, this can imply saving energy. If you bring water from far sources this requires energy, but using recycled water from nearby sources clearly is a better solution in terms of energy use. For now, we do not know the net implications. Assumptions are, though, that for cleaner water we will use more energy.
CWT: So to meet the water quality targets, treatment rates for both industrial wastewater and municipal sewage will increase, which could increase energy consumption in this sector.
Water use efficiency targets, on the other hand, could be achieved through improved water management and water conservation technologies. Management measures do not necessarily increase energy consumption. However, some of the low-water technologies, such as dry-cooling and hybrid cooling used in the power sector, have a relatively high “energy penalty,” increasing overall energy demand.
CWR: What do you see as the trade-offs between water usage and the need for energy?
CWT: The power sector is among the most water-intensive industries. Some power-generating technologies such as hydroelectric, geothermal, and concentrating solar power (CSP) have low greenhouse gas emissions but high levels of water consumption, while conventional coal-fired technologies have modest water usage but very high greenhouse gas impacts. For example CSP consumes 3-3.5 m3/MWh of water while a subcritical coal plant with a closed-loop cooling system only consumes around 1.6m3/MWh. Some alternatives, such as solar PV and wind power, can reduce onsite GHG emissions and water consumption to zero but are less economically competitive in the