SOLAR ENERGY: A Path to Energy Significance 4/12/12

DISPERSED PV GENERATION: SOLAR RESOURCE VARIABILITY

Richard Perez Tom Hoff

DISPERSED PV GENERATION: SOLAR RESOURCE VARIABILITY

SPATIAL

© R. Perez & T. Hoff

TEMPORAL TIME SCALE

© R. Perez & T. Hoff

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20 UNCORRELATED LOCATIONS

© R. Perez et al

Relative Variability = 1/√N N locations

© Richard Perez / Tom Hoff

Variability = σ(∆kt*)

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© R. Perez et al

© Richard Perez / Tom Hoff

Relative Variability = 1/√N N locations

© Richard Perez / Tom Hoff

16 Months of data -- 40 million data points

© R. Perez & T. Hoff

Virtual Networks Time space = f (cloud speed)

© Richard Perez / Tom Hoff

400x400km satellite-derived hi-resolution one-minute data

16 Months of data -- 40 million data points 16 Months of data -- 4 Billion data points

Very high density modular networks

66 stations

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© Richard Perez / Tom Hoff

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© Richard Perez / Tom Hoff

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© Richard Perez / Tom Hoff

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© Richard Perez / Tom Hoff

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HAWAII LAND Nov 2011 CLOUD SPEED 13 km/h

© Richard Perez / Tom Hoff

NEVADA Jun 1998 CLOUD SPEED 24 km/h

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© Richard Perez / Tom Hoff

HAWAII Dec 2010 CLOUD SPEED 26 km/h

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© Richard Perez / Tom Hoff

CENT. CALIFORNIA Mar 1998 CLOUD SPEED 30 km/h

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© Richard Perez / Tom Hoff

SOUTH GT. PLAINS Dec 2010 CLOUD SPEED 44 km/h

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Fluctuation Delta T (minutes)

© Richard Perez / Tom Hoff

∆t

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BASE GENERATION

VARIABLE GENERATION

SOLAR GENERATION STORAGE

CRITICAL TIME SCALE

Seconds Minutes Half Hour Hour

Small PV

Large PV or dist. feeder

Utility

Balancing Area

Application

Technical Solutions

Interconnection Hardware

Voltage reg. devices

Storage

Load Management, contingency variable generation

SolarAnywhere High Resolution

SolarAnywhere Standard Resolution

© R. Perez & T. Hoff

CRITICAL TIME SCALE

Seconds Minutes Half Hour Hour

SolarAnywhere High Resolution

SolarAnywhere Standard Resolution

© R. Perez & T. Hoff

Measured and simulated 10 second fleet output for a 4 km x 4 km region

© R. Perez & T. Hoff.

© Richard Perez / Tom Hoff

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20-Second fluctuations

1-minute fluctuations

5-minute fluctuations

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SINGLE POINT

© Richard Perez / Tom Hoff

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20-Second fluctuations

1-minute fluctuations

5-minute fluctuations

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SINGLE POINT

40x40 km AREA

© Richard Perez / Tom Hoff

Hourly Variability divided by 5

3-Hour Variability divided by 5

6-Hour Variability divided by 5

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Fluctuation Delta T (minutes)

∆t = 24 hours

Source: Marc Perez, Columbia University

∆t

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Dist

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Perez et al., ASRC

100oF

80oF

20oF

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60oF

© Richard Perez, ASRC

Early 2012 Heat Wave

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© R. Perez & T. Hoff

0.10 0.23 0.28 0.33 0.38 0.43 0.48 0.53 0.58 0.63 0.68 0.73 0.78 0.83 0.88 0.93 0.98 10 x10 km 0.3% 0.2% 0.2% 0.1% 0.1% 0.2% 0.2% 0.2% 0.3% 0.2% 0.5% 0.4% 0.6% 1.7% 3.9% 11.6% 79.2%

Clearness IndexDistributed

resource footprint

30x30 km 0.0% 0.0% 0.1% 0.1% 0.1% 0.1% 0.2% 0.3% 0.3% 0.4% 0.3% 0.4% 1.0% 1.9% 2.9% 7.5% 84.3%

70x70 km 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.6% 0.4% 0.8% 3.9% 94.4%90x90 km 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 2.0% 97.8%

110x110 km 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 2.7% 97.3%

50x50 km 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.0% 0.1% 0.4% 0.2% 0.4% 1.2% 97.6%

A/C Solar Peak Shaving Guarantee increases with resource distribution

15-year Clearness Index distribution for all hours with T >88F, Central CA

Probability of having less than a 90% ideal solar resource: ZERO

10x10km 30x30km 50x50km 70x70km 90x90km 110x110km

© R. Perez & T. Hoff

More intense cloud impact

More intense turbidity impact

FLAT PLATE vs. CONCENTRATION

Capa

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© R. Perez & T. Hoff

Thank you

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