Clack presentation for CO 2YC Energy Workshop

1. Decarbonizing the US Electricity Sector
Christopher T Clack Boulder CO, 14th Nov. 2015

2. 30
300
1940 1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 2050 2060
AnthropogenicAtmosphericCarbon
Dioxide(partspermillion)
Year
Observations
(278 ppm pre-industrial subtracted)
2 X CO2
Exponential Increase:
Doubling Time = 32 years
2 X CO2 = 2 x 278 ppm = 556 ppm
Year at 556 ppm ~ 2054
Post Industrial Carbon Dioxide Rise
When (years ago): 30,000 3M 20 M 40 M
Equilibrium climate: Pleistocene Pliocene Eocene
Image updated and adapted from PNAS paper, Hofmann, et al;
Solomon et al, Irreversible Climate Change, February 2009;
Beerling & Royer, Convergent Cenezoic CO2, Nature Geoscience, July 2011

3. The global circulation is a machine that is constantly running
This machine runs
constantly : any
“variability” is a local
phenomenon.
Transferring ~ 16 PW excess heat
from the tropics to the Poles

4. 1 2 4 5 6 71 3
Electric BAAs

5. The variability of wind increases by 5 times when area is
decreased by three orders of magnitude
Variability here is defined as the average coefficient of variation over a geographic region when divided up into isolated regions

6. My home (hyper-local) was under a snow storm in December
2014 that stopped solar production for seven days
Lost solar PV production for seven full days, while my energy demand increased sharply as it
was very cold. The average consumption over the period was 1 kW (used 168 kWh over 7
days), with peak hourly demand at 4.8 kW. Additionally, the wind was also very low in my area
at that time too.

7. Wind Capacity Factor Map

8. Wind Speed Video (m/s)

9. Solar PV Capacity Factor Map

10. Solar Irradiance Video (W/m2)

11. Wind Capacity Factor Map

12. Wind Speed Video (m/s)

13. Solar PV Capacity Factor Map
% % % %

14. HVDC Transmission Overlay

15. The Electric Power System in 2012
Documentation at http://www.esrl.noaa.gov/research/renewable_energy/news-simulator.html

16. US Aggregated Electric Demand
0
100
200
300
400
500
600
700
800
ElectricalDemand(GW)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
300
400
500
600
700
300
400
500
600
700
We know hour-by-hour what the electric demand is in ~130 regions across the
contiguous US for nine years (2006 – 2015)
* Load expanded by GDP, and then
by 0.7% per annum to 2030

17. Land Use Constraints
• The type and amount of electricity generation installed in each RUC cell is constrained by:
– Spacing between facilities
– Topography of the land
– Land Use (residential, commercial, protected lands, etc…)
Wind Solar PV

18. Cost Data – Can use different ones if you want to
see the changes
ethelow cost estimateisbased upon theoptimistic pricesin thestudiesreviewed. The
evaluesarethemean of thehigh and low prices.
re 11: The projected 2030 overnight capital costs including fixed O&M in 2013$ us
resent study.
The natural gas power plants are assumed to be a more mature technology. Therefore
useasinglecost for thenatural gaspower plantsin all threeof thepricescenarios, naNatural gas has a heat rate of 6430 Btu / kWh. Variable O&M is $3.31 / MWh
* * *

19. The Merit Order Effect
This is a market
and these are bids

20. Mathematical Optimization (Simplified)
= + + + +
Minimize:
+ - ≥
Subject to:
ALL OTHER EQUATIONS CONSTRAIN THE MAGNITUDE OFANY OF THE TERMS

21. A “national” US system that is cost optimal for 2030
Demand up 18%
79.2% Carbon Free
8.4¢ / kWh

22. Cost optimized US Electric Power System for 2030
Dispatch Stack
0 168 336 503 671 839
Time (Hrs)
0
200
400
600
800
Generation&Load(GW)
Dispatch Stack
3648 3816 3984 4151 4319 4487
Time (Hrs)
0
200
400
600
800
Generation&Load(GW)
Retail Cost of Electricity
$83.82 / MWh

23. With this detailed study we find increasing area will incorporate
more wind and solar, while costs will decrease

24. As the cost of natural gas fuel increases, so does the penetration of
wind and solar PV
$-
$0.02
$0.04
$0.06
$0.08
$0.10
$0.12
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
$2.00 $3.00 $4.00 $5.00 $6.00 $7.00 $8.00 $9.00 $10.00 $11.00 $12.00 $13.00 $14.00
AverageCostofElectricity(2013$/kWh)
Shareofelectricdemand(%)
Natural gas fuel price (2013$ / MMBtu)

25. NEWS Result: Single US 48 States Electric Power System
(Low Cost Renewables, High Cost Natural Gas)
200 250 300 350 400
Time (Hrs)
0
200
400
600
800
Generation/Load(GW)
4000 4050 4100 4150 4200
Time (Hrs)
0
200
400
600
800
Generation/Load(GW)
Carbon-Free Instantaneous Penetration Level Histogram
20 40 60 80 100 120
Percentage of Load Met (%)
0
2
4
6
8
10
12
PercentageofTime(%)
Dispatchable Instantaneous Penetration Level Histogram
0 20 40 60 80
Percentage of Load Met (%)
0
5
10
15
20
PercentageofTime(%)
-60 -40 -20 0 20 40 60
Ramp Rate per hour (%)
0
10
20
30
40
Percentageofthetime(%)
Capacity
Generation

26. NEWS Result: 128 Independent Electric Power Systems
(Low Cost Renewables, High Cost Natural Gas)
200 250 300 350 400
Time (Hrs)
0
200
400
600
800
Generation/Load(GW)
4000 4050 4100 4150 4200
Time (Hrs)
0
200
400
600
800
Generation/Load(GW)
Carbon-Free Instantaneous Penetration Level Histogram
20 40 60 80 100
Percentage of Load Met (%)
0
2
4
6
PercentageofTime(%)
Dispatchable Instantaneous Penetration Level Histogram
0 20 40 60 80
Percentage of Load Met (%)
0
2
4
6
PercentageofTime(%)
-60 -40 -20 0 20 40 60
Ramp Rate per hour (%)
0
10
20
30
40
Percentageofthetime(%)

27. Dispatch of wind and solar PV shows the dynamics of the system, with the generators
working in concert with each other over the large region

28. Simpler Global Regions

29. Assuming the electricity grid can grow in size, the amount of wind
and solar installed increases and cost of energy decreases
Utilization of Wind and Solar (Low RE, High NG)
104
105
106
107
Area (km2
)
0
20
40
60
80
100
Carbon-FreeGeneration(%)
USA
Europe
China
Australia
Total Annual Cost of the System (Low RE & High NG)
104
105
106
107
Area (km2
)
0
10
20
30
40
50
Differencecomparedwithlargestdomain(%)
The increase in installed capacity and reduction in costs are influenced by a number of factors:
• The total energy demand required
• The wind and solar resource, its location and its proximity to population
• The data used in the model (weather resolution, load profile, transmission, etc.)

30. Capacity Factor Maps
0% 66%33%
Africa Wind Capacity Factor (80 m – IEC-III)

31. Capacity Factor Maps
22% 38.5%30.25%
Africa Solar PV Capacity Factor (17% efficiency)

32. If each country works on its own energy solution without coordination with other
nations the cost optimal mix is 55% wind and solar over the continent
Taken into account:
• Individual Countries
• Land area
• Water
• Population Space
• Weather resource
• Technology
• Energy demand
• Cost Optimal
CO2: 974.9 mmT
Cost: 8.1¢ / kWh
Wind: 434.3 GW (29.0%)
PV: 575.2 GW (26.2%)
Natural Gas: 886.9 GW (44.8%)
Curtailment: (7.3%)
Not taken into account:
• Storage
• Other technologies
• Transmission
• Existing infrastructure

33. If the African continent combined their resources and grids
the wind and solar levels goes to 93% for lower cost
Taken into account:
• Individual Countries Combined
• Land area
• Water
• Population Space
• Weather resource
• Technology
• Energy demand
• Cost Optimal
CO2: 160.3 mmT
Cost: 5.2¢ / kWh (35.8% decrease)
Wind: 1125.0 GW (85.1%)
PV: 139.8 GW (7.6%)
Natural Gas: 384.9 GW (7.4%)
Curtailment: (11.3%)
Not taken into account:
• Storage
• Other technologies
• Transmission
• Existing infrastructure

34. The African continent has a very large area, and accordingly the
variability is lower and that drives an increase in wind and solar
Utilization of Wind and Solar (Low RE, High NG)
104
105
106
107
Area (km2
)
0
20
40
60
80
100
Carbon-FreeGeneration(%)
USA
Europe
China
Australia
*

35. When you have small areas the variability is much
greater than over a larger aggregated region
Dispatch Stack
0 168 336 503 671 839
Time (Hrs)
0
200
400
600
800
1000
Generation&Load(GW)
Dispatch Stack
3648 3816 3984 4151 4319 4487
Time (Hrs)
0
200
400
600
800
1000
Generation&Load(GW)

36. The larger geographic area allows much more wind and
solar to be integrated cost effectively
Dispatch Stack
0 168 336 503 671 839
Time (Hrs)
0
200
400
600
800
1000
Generation&Load(GW)
Dispatch Stack
3648 3816 3984 4151 4319 4487
Time (Hrs)
0
200
400
600
800
1000
Generation&Load(GW)

37. Questions / Discussion / Further work