Nebraska meetingNovember 19, 2007

Brian Parsons

Brian_parsons@nrel.gov

Transmission and Wind Energy

Wind Systems Integration at NREL• National Wind Technology Center• Systems Integration Team• Bulk power focus (not Distributed Interconnection)• Advising PUCs and the power industry as technical

reviewers to integration studies• Participate in regional transmission, integration studies• Data resource and methods development

• RTO frameworks evolving• Issues

• Cost allocation:• projects vs. network• Reliability vs. economy

• Cost recovery• Siting and permitting• Development timing:

chicken and egg problem

Transmission is an issue for all new generation

Transmission and WindIf you love wind, you have to at least like transmission• Wind is location constrained – good wind not necessarily close

to existing transmission• Issues:

– Build transmission if generator requests, but wind can’t get financing unless transmission exists

– Wind build times shorter than transmission but wind projects smaller than transmission

• Long-term wind buildout: single larger line more cost-effective than several smaller lines

• Transmission is a public good

These issues have been ‘solved’ in Texas with CREZ process

Renewable Energy Zones/Build Transmission First

• Initiated by Texas Competitive Renewable Energy Zones

• Colorado Energy Resource Zones• California Renewable Energy Transmission

Initiative• Southwest Area Transmission Renewable

Energy Task Force (Arizona, New Mexico, Southern Nevada, Southeastern California)

• Broader regional study proposed for Western Governor’s Association

Large Transmission Investments Have Very Small Retail Bill

Impacts

$13.38 $13.38

$48.66 $48.66

$3.71 $4.58

0

15

30

45

60

75

CurrentAverage

Monthly Bill

Retail bill withAdditional TxInvestment

$ /

1,0

00 k

Wh

Average Monthly Retail Bill $ / 1,000 kWhs

Total $65.75 Total $66.62

Transmission 6%

Generation 74%

Distribution 20%

Impact from $12.6 billion increase

(20%) in Transmission Infrastructure

Source: FERC

Balancing Authority Cooperation• Northern Tier

Transmission Group: Area Control Error (ACE) sharing agreement

• WestConnect: virtual balancing area consolidation study and transmission rate de-pancaking experiment

NTTG

WestConnect

FERC 890 Ruling – Impacts for Wind Integration• Eliminates Imbalance penalties for wind and

solar• Establishes conditional firm as part of the

OATT in non-Independent System Operator areas– 2 year contract term limits value– Transmission provider must define and quantify

periods of potential curtailment, possible basis includes system conditions, or hours of month

– Conditional firm concepts and products under development by grid entities

• Requires consistency, standards, and transparency of ATC calculations

• Makes regional planning mandatory

FERC Grid Code and WECC • FERC final order 661/661a

– Issued 12/05– Allows regional variation

• Low Voltage Ride Through – Phased in standard– WECC now considering zero

voltage for 9 cycles, with recovery slope, and is adding a High Voltage standard

• VAR control: +/- 95% if grid study shows a need

• SCADA req. defined

Voltage Ride Through

0

0.2

0.4

0.6

0.8

1

1.2

1.4

-1 0 1 2 3 4

Time (sec)

Volta

ge (p

.u.)

661

661A

LVRT-WECC Prop.

HVRT-WECC Prop.

Code specifics are still evolving, but largely mitigate stability issues

Vision: 20% of electric energy from Wind• Over 300 GW of new wind plants, 7+ GW in Kansas• Existing transmission system is inadequate• Conceptual 765 kV EHV overlay examined by AEP• $60 billion over 20 yrs• 19,000 mi of line • Delivers additional 200-400 GW• Current transmission investment $7 billion/yr and growing

No fundamental technical barriers to the integration of 20% wind, but There needs to be a continuing evolution of transmission planning and system operation policy and market development

Forums• UWIG: Nebraska utilities are members, but engineers are not active www.uwig.org • AWEA Transmission and Turbine O&M groups• DOE/NREL Wind Powering America Program state activities•National Wind Coordinating Collaborative

•South Dakota meeting, November 29-30, Sioux Falls

Eastern Wind Integration Study