Ownership Change, Incentives and Plant Efficiency: The Divestiture of U.S. Electric Generation Plants James Bushnell UC Energy Institute Catherine Wolfram UC Berkeley Tenth Annual POWER Research Conference March 18, 2005 Berkeley, CA
Dec 21, 2015
Ownership Change, Incentives and Plant Efficiency:
The Divestiture of U.S. Electric Generation Plants
James BushnellUC Energy Institute
Catherine WolframUC Berkeley
Tenth Annual POWER Research ConferenceMarch 18, 2005 Berkeley, CA
Electric generating plant divestitures
• The ownership of electric generating plants in the U.S. changed dramatically between 1998 and 2001.
- Over 300 plants, representing nearly 20% of U.S. installed generating capacity, changed ownership.
• Divestitures were encouraged by state regulators as part of the industry restructuring.
- Easy measure of stranded costs.
- Addressed concerns about the ability of a firm that was vertically integrated into transmission to exercise market power.
• Old owners (investor owned utilities) faced cost-of-service regulation; new owners face market incentives.
Electricity industry restructuring and economic efficiency
• There is heated debate in academic and policy circles about how to design restructured markets.
• All of this should be moot if restructuring doesn’t improve economic efficiency.
• Several academic and policy studies have examined the effects of restructuring on cost efficiencies:
- Top down: DOE (2003), SEARUC (2003), CAEM (2004).
- Bottom up: Markiewicz, Rose and Wolfram (2004) looks at changes in operating efficiency at IOU plants facing new incentives; Kleit and Reitzes (2005) looks at dispatch efficiency.
Measuring the effects of divestitures on plant efficiency
• Ideally, we would like to evaluate changes in each plant’s total factor productivity after divestiture.
• Unfortunately, data on employment, maintenance and capital inputs is not publicly available after divestiture.
- We’re exploring data availability from various sources.
• For now, we’re analyzing whether fuel efficiency changed at plants that were divested.
- Rich data are available from the Environmental Protection Agency.
- Implicit assumption that production is Leontief in fuel and other inputs.
There may be no effect of divestiture on fuel efficiency
- A generating unit’s fuel efficiency is an immutable technological characteristic.
- IOUs may have made poor investment decisions, but at least they knew how to operate their own plants.
…or there may be either positive or negative net effects.
• Heat rates could go up following divestiture.
- It will take the new owners some time to master the idiosyncrasies of the plant.
- New owners may cycle the plants more (e.g. to exercise market power) at the cost of higher heat rates.
• Heat rates could go down following divestiture.
- IOUs had fuel adjustment clauses, so they didn’t do everything possible to minimize heat rates.
- New owners might be able to renegotiate union contracts so they can promote good operators.
Data set
• We are analyzing electric generating units that are:
- Fossil-fuel fired (i.e. not nuclear or hydroelectric).
- Included in the EPA Continuous Emissions Monitoring System data base.
- In regions where divestitures were prominent (this excludes, for instance, all the plants in Florida).
• We have hourly fuel input and output data on ~1000 generating units for 7 years (1997-2003).
We analyze plants in the shaded states.
Empirical specification
• To analyze divestitures, we estimate versions of the following equation:
• for unit i in time period t, where
- HR is the unit’s heat rate (inverse of fuel efficiency),
- t is either monthly or hourly,
- Divestiture = 1 after divestiture (if applicable),
t are month dummies, θi are unit dummies, and
- we specify the relationship between HR and Gross Load with care.
ituniti
monthtititit GrossLoadeDivestiturfHR ,,),ln(,)ln(
Example of what we’re labeling a Divestiture effect.
Unit
Year
Divested Not divested
1997 14 11
2003 12 10
Average Heat Rates for 2 units across 2 years
Example of what we’re labeling a Divestiture effect.
Unit
Year
Divested Not divested
1997 14 11
2003 12 10
Our Divestiture effect:
(12-14) – (10 -11) = -1
Average Heat Rates for 2 units across 2 years
Our estimates control for:
- differences in average heat rate levels across
divested and not-divested units.
- general trends in heat rates.
Example of what we’re labeling a Divestiture effect.
Unit
Year
Divested Not divested
1997 14 11
2003 12 10
Our Divestiture effect:
(12-14) – (10 -11) = -1
Average Heat Rates for 2 units across 2 years
Our estimates control for:
- differences in average heat rate levels across
divested and not-divested units.
- general trends in heat rates.
Our Divestiture effect in logs:
(ln(12)-ln(14)) –
(ln(10) –ln(11)) -.05
The basic Divestiture effect: 2% reduction in Heat Rate
Dependent Variable: ln(Heat Rate)
OLS IV
Only Divested
UnitsWith
Controls
Only Divested
UnitsWith
Controls
Divestiture -0.022** -0.021** -0.022** -0.013
(0.010) (0.010) (0.009) (0.009)
ln(Q) -0.405*** -0.364*** -0.380*** -0.106
(0.024) (0.018) (0.068) (0.120)
Month-Year Fixed Effects No Yes No Yes
Unit or Unit-Interval Fixed Effects Unit Unit Unit Unit
R2 .56 .54
N 22,506 75,066 19,501 64,882
See Table 4 in the paper.
Why do we see lower heat rates after divestitures?
• Utilities only sold plants that were ripe for improvements.
In states with major divestitures, IOUs sold nearly all their thermal capacity.
StateTotal Fossil
Fuel MW IOU % in 2003
CA 36600 2%
CT 5750 0%
DC 590 0%
DE 3084 0%
IL 32486 5%
MA 11983 0%
MD 10373 1%
ME 2860 0%
MT 2448 6%
NJ 15258 4%
NY 28196 19%
PA 33424 5%
StateTotal Fossil
Fuel MW IOU % in 2003
IN 26342 71%
KY 19482 49%
NH 2523 43%
OH 32782 55%
VA 16501 63%
Why do we see lower heat rates after divestitures?
• Utilities only sold plants that were ripe for improvements.
Why do we see lower heat rates after divestitures?
• Utilities only sold plants that were ripe for improvements.
• Utilities deferred maintenance before they sold the plants; merchant firms have been regaining lost ground.
Why do we see lower heat rates after divestitures?
• Utilities only sold plants that were ripe for improvements.
• Utilities deferred maintenance before they sold the plants; merchant firms have been regaining lost ground.
- But we find no evidence of heat rates deteriorating before the divestitures (see Table 7).
Why do we see lower heat rates after divestitures?
• Utilities only sold plants that were ripe for improvements.
• Utilities deferred maintenance before they sold the plants; merchant firms have been regaining lost ground.
• Merchant firms faced new incentives—incentive effect.
• New owners shook things up—ownership effect.
Table 7: evidence on incentive and ownership effects
IOU plants showed improvements in states with rate freezes,
suggesting incentives matter.
Evidence on effects of ownership transfers less clear.
Dependent Variable: ln(Heat Rate)
OLS
All Units
All Units
Divestiture -0.024** (0.011) External Only -0.003 (0.013) External Both -0.023 (0.018) Internal Subsidiary -0.067*** (0.024) Incentive Regulation -0.019** -0.019* (0.010) (0.010) ln(Q) -0.364*** -0.364*** (0.018) (0.018) Month-Year Fixed Effects Yes Yes R2 0.54 0.54 N 75066 75066
Why do we see lower heat rates after divestitures?
• Utilities only sold plants that were ripe for improvements.
• Utilities deferred maintenance before they sold the plants; merchant firms are regaining lost ground.
• Merchant firms faced new incentives—incentive effect.
• New owners shook things up—ownership effect.
What’s being done differently at divested plants?
• Are merchant firms operating at the “sweet spot” more?
• Are merchant firms changing other aspects of operations (combustion optimization software, fuel switching, etc.)?
Unit heat rate profiles
5
7
9
11
13
15
17
19
21
23
25
0 2 4 6 8 10 12 14 16 18 20 22
Capacity Interval
Ave
rag
e H
eat
Rat
e (m
mB
tu/M
Wh
)Overall < 100 MW > 100 MW
Implied magnitude
• Our estimates suggest that plants have ~2% lower heat rates after the divestiture.
• At current fuel prices, this amounts to about $0.6/MWh.
- At the plants that were divested, this adds up to savings of nearly $500 million per year.
- Scaling this up to all thermal plants nationwide, this could add up to almost $1.5 billion per year.
• Improving fuel efficiency helps achieve environmental goals,
especially with respect to CO2
Conclusions
• In light of the California electricity crisis, it is useful to remind ourselves about the potential efficiency gains of restructuring.
• This paper focuses on fuel efficiency at existing generating plants.
• Evidence is positive—owners respond to incentives.
• Additional efficiency gains possible through:
- More efficient long-term (capital) investment.
- Incentive regulation for transmission and distribution.
- Reallocating output across plants.