Energy Conservation and Emissions Reduction: Experiences from Three Provincial Power Companies and One Regional Power Grid Company

Power industry is one of the key fields for energy conservation and emissions reduction (ECER) in China. In order to achieve the nation's overall energy consumption target and pollutant emission target set by the 11th Five-Year Plan, to build the resource-conservation and environment-friendly society during the 11th Five-Year Plan period (2006-2010), it is crucial to implement the policy of "Large (units) In and Small (units) Out (LISO)" (i.e., replacing small units with large ones) and accelerate the retirement of small thermal units. According to the statistics, the power industry has made a significant progress in SO2 emission reduction during the first half of 2007. Specifically, with 18.3% growth in power generation, the SO2 emission was reduced by 5.2% compared with the same period in 2006. By the end of July 2007, the retired small units have totaled 6950 MW, 85% of which belongs to the five major power generation groups such as Guodian and Huadian. In this article, the achievements and remaining issues in Henan, Jiangsu, Sichuan Power Companies and East China Grid Company were presented and discussed thoroughly.

Optimal placement of PMUs for the smart grid implementation in Indian power grid A case study

Efficient utilization of energy resources is essential for a developing country like India. The concept of smart grid （SG） can provide a highly reliable power system with optimized utilization of available resources. The present Indian power grid requires revolutionary changes to meet the growing demands and to make the grid smarter and reliable. One of the important requirements for SG is the instantaneous monitoring of the voltage, current and power flows at all buses in the grid. The traditional monitoring system cannot satisfy this requirement since they are based on nonlinear power flow equations. Synchro-phasor-measurement devices like phasor mea- surement units （PMUs） can measure the phasor values of voltages at installed buses. Consequently, the currents passing through all branches connected to that bus can be computed. Since the voltage phasor values at the neighboring buses of a bus containing the PMU can be estimated using Ohm＇s law, it is redundant to install PMUs at all the buses in a power grid for its complete observability. This paper proposes the optimal geographi- cal locations for the PMUs in southern region Indian power grid for the implementation of SG, using Integer Linear Programming. The proposed optimal geographical locations for PMU placement can be a stepping stone for the implementation of SG in India.

Optimal redundant placement of PMUs in Indian power grid -- northern, eastern and north-eastern regions

Effective utilization of renewable energy sources and efficient management of electric energy are essential for any developing countries like India. This can be envisioned through the implementation of concepts of smart grid （SG）. One of the key requisites for SG implementation is that the grid should be completely observable. Renovation of conventional Indian power grid to a SG necessitates incorporation of the phasor measure- ment units （PMUs） in the present power grid measurement and monitoring system. Since the cost of PMU is high and any bus containing a PMU makes the neighboring connected buses observable, optimal placement of PMUs is very important for complete observability of the grid. This paper proposes optimal redundant geographical locations in the northern, eastern and north-eastern regions of Indian power grid for PMU placement. The PMUs installed in these geographical locations will make the grid completely observable and maintain the observability under the conditions of failure of some PMUs or branch outages. Integer linear programming has been used for finding the optimal PMU locations. The results proposed in this paper can be a stepping stone for revamping the Indian power grid to a SG ensuring complete observability during different contingency conditions.