Kevin Porter and Sari Fink
凯文 波特，莎莉 芬科
Exeter Associates公司
Energy Foundation Meeting on Wind Integration
能源基金会美国并网经验介绍会
Beijing, China
June 2010
Outline
提纲
• Introduction 简介
• Examples of Wind Curtailment 弃风案例
 Generator interconnection 并网
 Contractual 协议
 Bid-based curtailment 招标法弃风
 Daily operating limits 日常运行限制
 By type of wind technology 依据风电技术类型
 Amount of available reserves 备用电源量
• Compensation 补偿
• Curtailment Data 弃风数据
• Conclusions 结论
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Introduction 简介
• Wind power development has
•
increased dramatically over the last
decade, while transmission investment
in many regions has failed to keep pace.
• Additionally, wind facility construction
•
times are much shorter than for
transmission.
• Wind may blow stronger at night when •
loads are low.
• This has resulted in situations where
wind energy production can at times •
exceed the electricity system’s ability to
operate reliably.
• Curtailment of wind energy has
•
increased as a result.
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风电在过去的十年中发展非
常迅猛，然而在很多地方输
电投资却跟不上
而且风电场建设所需时间远
低于输电设施建设的时间
夜晚用电负荷低的时候，风
资源却偏偏更好
这导致，有些时候，风电会
超出电力系统的接纳能力，
危及电网的安全运行
弃风成为无奈的选择
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Why Important for China
对中国的重要意义
• Significant international
• 重要的国际弃风经验和
experience and
实验
experimentation with wind • 这些国际经验可以从发
curtailment.
电端和电力系统两个方
• International experience
面提供有用的参考
can provide useful
experience from both
system and generation
perspective.
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Curtailment Data
弃风数据
•
•
Curtailment data can be difficult to acquire as
there are seldom requirements in place for
reporting it.
The table below gives some data for various
jurisdictions.
• 缺少相关规定导致弃风数据难
以获取
• 下表给出不同地区的一些数据
Entity单位
Curtailment Data弃风数据
BPA
As of March 30, 2010, total cumulative capacity of wind that has been limited is 2900 MW.
ERCOT
In 2009, curtailed on average around 500 to 2,000 MW daily, max amount approximately 3,900 MW.
ERCOT curtailed about 16% of wind generation in 2009.
Midwest ISO
In 2009, around 1,100 incidences of wind curtailment totaling about 200,000 MWh, representing about 1%
of total wind generation.
SCE
About 15 MW for 3-4 hours every two days from a single wind plant in Tehachapi (contractual arrangement).
Xcel
In 2009, 42,359 MWh of wind generation in Minnesota and 18,991 MWh of wind generation in Colorado
were curtailed.
Alberta ESO
Curtailed wind for about 838 hours in 2009.
Denmark
May curtail over 20% of marginal wind production
Germany
Between 2004 and 2006, approximately 74,000 MWh of wind energy was curtailed.
Ireland
In 2008, approximately 100 MWh of wind energy was curtailed.
Spain
In 2009, approximately 54,000 MWh of wind curtailed, or about 0.15% of total wind production. Expected
to increase dramatically to as much as 6.8%.
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Condition of Generator Interconnection
并网情况
•
Wind generators connecting to the grid
are required (like all generators) to
execute interconnection agreements.
• These interconnection agreements can
include clauses whereby wind facilities
agree to curtail generation, on request
from the grid operator, if transmission
constraints or system conditions require
it.
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•
与其他电力供应商一样，联网项目的风电
供应商也被要求执行并网协议.
•
并网协议会有一些条款，规定受输电条件
约束或系统条件制约的情况下，电网运营
商可以要求风电供应商弃风，风电供应商
要接受。
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Contractual
协议
•
•
Some individual utilities include wind
curtailment conditions in power purchase
agreements.
Under these agreements, wind facilities
often provide a set amount of wind
generation curtailment for a specified
amount of time each year at no cost or
reduced cost to the purchasing utility.
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•
部分电力公司在购电协议中添加了弃风条
款
•
依据这些协议，风电场方面常常是就一个
每年特定时长内无补偿或低补偿的固定弃
风量和购电方进行约定。
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Market Bid-Based
市场招标制
•
Some regions with wholesale energy markets are
integrating wind energy into their economic
dispatch.
•
一些地区的电力批发市场正在把风电纳入其经济调
度的范围
Wind generators bid price curves into wholesale
markets indicating at what prices and amounts they
are willing to generate.
•
•
•
•
•
•
风电供应商在电力批发市场中以“价格曲线”的形
式投标售电，这可以揭示出他们能够接受的最低价
格和数量水平
Due to tax credits/incentives in United States, wind
plants may want to produce at negative prices.
由于美国的税收优惠/激励政策，风场有可能愿意接
受“负电价”发电
Prices may fall to point that wind economically
curtails.
价格下降到一定程度风电供应商就会选择弃发。
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Daily Operating Limits
日常运行限制
• Some grid operators have
imposed daily operating limits on
wind farms.
• 一些电网运营商设定了风场每日
运行限制
• This is generally done on an areaspecific basis when there is a
concentration of wind plants
developed in a single
transmission constrained region.
• 这种限制通常发生在风电场分布
密集且电网线路能力有限的区域
• Wind plants must match their
output to the daily limit.
• 风场须按照当日限制生产。
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Differentiated by Technology
按不同技术种类
• Wind technology has evolved
quickly over the last decade.
• 风电技术在过去十年发展很快
• Newer wind plants have more
advanced control capabilities.
• 新建的风电场比原来的有更强的
控制能力
• Some grid operators have taken
advantage of the advanced
control capabilities for faster
response to system events.
• 一些电网运营商已经从先进的控
制技术上受益，能够更快的响应
系统变化。
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Availability of Reserves
可用的备用电源
• Some grid operators have tied
wind curtailment to the
availability of generation reserves.
• 一些电网运营商已经把备用电源的
情况和弃风联系到了一起
• When generation reserve use
reaches a set level, wind is asked to
curtail production to the lower of
their scheduled amount or actual
operating amount.
• 当备用电源的使用达到了一定程度，
风电就得应要求弃发一定比例，降
低发电量。
• This reduces the need to acquire
additional reserve generation.
• 这样可以减少对备用电源的需求
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Compensation
补偿
•
Compensation for lost energy production
varies by jurisdiction both within the U.S. and
outside the U.S.
• Direct compensation especially important if no
limits are placed on amount of curtailment
• Compensation can also be differentiated by the
reasons for the curtailment.
• Situations where wind plants may not be
directly compensated include:
 Curtailments may be covered by contract
or by agreement.
 Curtailments are due to a system
emergency or reliability event where all
generation may be curtailed.
 Transmission constraint was caused or
aggravated by the curtailed wind plant.
 Curtailment is the outcome of a marketbased economic dispatch process (i.e., by
virtue of market bids, wind curtailment
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was theInc.
most economic option to curtail).
•
弃风补偿在美国各地或其他国家都
不尽相同
•
如果没有对弃风量的约定，直接补
偿就变得尤为重要
•
因弃风原因的不同，补偿高低也不
一样
一些不能得到直接补偿的情况
•
 在合同或协议中已经约定好的弃风
部分。
 因系统紧急状况或可靠性问题的出
现而导致电源全部弃发。
 个别风场引起或加剧了输电压力的
情况下，这些风场须接受的弃发。
 弃风是市场机制下经济调度的结果
(比如, 在市场出价规则下，让风电
来弃发是最经济的一种选择).
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Compensation (cont.)
补偿
•
When provided, compensation amounts can be
determined in various ways. Examples include:
 ERCOT paid out-of-merit energy payments
for curtailments in real-time.
 Southern California Edison provides make
whole payments for energy.
 Xcel Energy provides make whole
payments for both fixed and variable wind
plant costs in Minnesota and make whole
payments, including the Production Tax
Credit, for curtailments in Colorado that
are above the contracted amounts.
 Germany provided payments equal to lost
revenues.
 In Ireland, curtailed wind plants are paid
in the energy markets as if they generated
at full available output.
 In Spain, compensation for real-time
curtailments is a percentage of the
wholesale price of electricity, currently set
at 15%.
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•
一些情况下弃风可以得到补偿，补偿金额的确
定有多种方法。比如:
 ERCOT 为优选顺序外，实时调度的弃风量
提供补偿。
 南加州爱迪生公司采用“能源整付”办法.
 Xcel 能源在明尼苏达州采取对风电给予固
定成本和可变成本整付的方案，在科罗拉
多州采取协议外弃风量给予包括生产税抵
减优惠在内的整付方案。
 德国根据实际经济损失给予等额补偿。
 在爱尔兰，能源市场为风电场的弃风损失
提供补偿，核定弃风时风场可实现的全额
实发量，据此给予补偿。
 在西班牙，实时弃风补偿根据电力批发售
价的一定比例给予，现行的比率是15%。
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Conclusions
结论
•
•
Amount of wind curtailment is likely to rise in
the United States, China and elsewhere, at least
until transmission issues are resolved.
If curtailments are necessary the following
principles should be incorporated into
curtailment initiatives:





Grid operators should ensure that all actions that can
be taken have been taken prior to curtailing any
generation, such as ensuring all generation that has
non-zero operating costs are running at minimum,
imports have been reduced or eliminated, and export
opportunities have been exhausted.
If curtailments are necessary, wind should be treated
comparably with all generation. Wind should not be
curtailed just because it is easy to do so.
To the extent that markets allow/exist, wind generators
(along with all generators) should have the
option/ability to bid in prices at which they are willing
to be curtailed.
Issue of whether generators (including wind) should be
paid if curtailed (and how much) needs to be addressed.
If not directly compensated, need to find ways to limit
exposure to financial risk.
Other measures to reduce curtailment include large
balancing areas, dynamic scheduling and dynamic
ratings of transmission lines.
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•
在电力送出问题解决之前，无论是美国还是中国
或者其他国家、地区，弃风量都存在继续增加的
可能。
•
当必须执行弃风管理的时候，以下原则应考虑在
内:





电网运营商应确保在弃风前已经采取一切可能的措
施,比如确保所有以“非零”运行成本发电的电源
已经调整到最低运行状态，对外来电力的吸收已经
销减甚至取消，而向外送电的能力已经用尽。
如果弃风不可避免，也要对风电和其他电源一视同
仁。不能仅仅因为风电弃发容易而让它弃发。
在市场允许的程度内，风能发电商（及其他发电商）
应该有选择投标其能接受的弃风价格的权利。
需要解决发电商（包括风电）弃发是否应得到补偿
（及补偿多少）的问题。如果无法直接补偿，也要
找到可以约束经济风险比率的办法。
其他减少弃风的办法还有大区域管理、动态调度和
动态输变线路载荷评定等。
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Report
报告
• Full report is at
• 完整报告可从以下链接获取
http://www.nrel.gov/docs/fy10osti/46716.pdf.
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Kevin Porter
Exeter Associates, Inc.
10480 Little Patuxent Parkway, Suite 300
Columbia, MD 21044
410-992-7500
410-992-3445 fax
kporter@exeterassociates.com