Operations of Electric Power Systems with High Penetration of Wind Power: Risks and Possible Solutions

Abstract

Abstract-This paper provides an assessment of wind power effects on technical and economic performance of today's electric power systems. While a small penetration of wind power is unlikely to cause any qualitative changes, significant deployment of wind-generated power will require a major rethinking of generation dispatch and automatic generation control, in particular. We summarize technical risks, as well as the economic implications on total cost of providing power to customers. The discussion is presented for both traditional fully regulated utilities and for the portions of the electric power interconnection which are undergoing restructuring. The paper suggests that the ultimate benefit of wind power to the customers will depend to a large extent on how well today's operating practices are adjusted to make the most out of the available resources, including the intermittent wind power. Moreover, we suggest that an analysis should be done to determine the amount of wind power for a given system beyond which benefits are difficult to capture because of the necessary additional infrastructure cost.

‘Good’ or ‘bad’ wind power forecasts: a relative concept

“…28 For instance, in cases where the SO defi nes the reserve requirements on the basis of deterministic criteria, the awareness of this overestimation may lead to a highly conservative attitude and an adoption of high safety margins to minimize the risk-and will therefore heavily increase the operational costs. Also, as mentioned in Ilic et al, 29 imbalances may aggravate potentially large out-of-merit automatic generation control costs. All of these operational costs will be part of the tariff paid by all customers.…”

Transmission System Operation Challenges with Large Wind Penetration

“…As the source BA, BPA provides Generation Imbalance Service, by default, 2 for IPPowned wind facilities; even though most of the wind is exported from Bonneville's BA, thus obligating BPA to carry a large amount of regulation reserve. Regulation reserve (regulation, load following, and generation imbalance 3 ) is provided from Federal Hydro Projects. Federal Hydro Projects include 31 dams on the Columbia River and its tributaries, with a total nameplate rating of installed hydro generation capacity of 20,430 MW.…”

“…Management of hydro projects is very complex and subject to many constraints based on the Endangered Species Act (which requires flow to 2 FERC Order 890, Schedule 9. 3 Generation Imbalance is an integral of Scheduled MW flow minus Actual MW flow over one clock-hour period. support fish migration and spawning) and the Clean Water Act (which imposes minimum generation conditions).…”

Use of wind power forecasting in operational decisions.

“…For instance, in cases where the SO defines the reserve requirements on the basis of deterministic criteria, the awareness of this overestimation may lead to a highly conservative attitude and an adoption of high safety margins to minimize the risk -and will therefore heavily increase the operational costs. In addition, as mentioned in [33], imbalances may aggravate potentially large out-of-merit automatic generation control (AGC) costs. All of these operational costs will be part of the tariff paid by all customers.…”