Wind’s Rise to Dominance: The Economic and Technology Basis
- Nov 28, 2018 7:23 pm GMT
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Wind’s Rise to Dominance: The Economic and Technology Basis
Charles Botsford, P.E., Monrovia, Calif.
We have used wind as a power source for millennia. How else to sail the oceans and master new frontiers? A mere four thousand years ago, we developed windmills to pump water and grind our grain. Wind has been a vital power source in the history of civilization.
Over a hundred years ago, we developed wind turbines to generate electricity. In the 1980s, the wind industry in Southern California was tax shelter driven. The turbines were tiny by today’s standards, the technology shaky, and the economics dismal—except for artificially high utility contracts.
Things have changed…dramatically. The economics and technology of wind have improved, and continue to improve.
The Bounty, c.1996, source: Abbot
Wind’s rise to the dominant power source worldwide progresses unchecked. Coal and nuclear are on the inexorable decline. Natural gas – subject to global volatility over the last decade – is on the upswing, but for how long? Solar, too, is on the upswing, and has a major role as wind’s partner in the future of renewable power generation. However, this discussion centers on wind.
How has wind done it?
Power Generation Economics
The method to test the economics of power generation are by executing power purchase agreements (PPAs), which are typically long-term contracts, or by bidding power into a market such as PJM, which are typically much shorter-term contracts.
If the PPA price is higher than the overall cost to produce power, the generator can make money. Likewise, if the power generator can bid their power into a utility market, and the bid clears the highest cost threshold, then the market will use the power, and the generator is paid for the power. If the bid amount covers the overall cost to produce the power, including operations, then the generator can make money. The national average for a land-based wind PPA in the US is about $20/MWh. The US’s first commercial scale offshore wind farm (Vineyard Wind’s 800MW project planned for Massachusetts) is to be priced at about $65/MWh.
What goes into the ultimate cost of power generation?
- The capital cost to build the power plant, or Capex
- The operational cost, including fuel, or O&M, and
- The capacity factor
The U.S. Department of Energy, and others, use a metric called, Levelized Cost of Electricity (or Energy), or LCOE. LCOE is the total cost of generating electricity, denoted by dollars per megawatt-hour ($/MWh) over the lifetime of the generation source. It provides a simplified way of comparing the generation-side economics of power generation sources such as natural gas, solar, coal, nuclear, land-based wind, offshore wind, and others.
According to DOE’s Energy Information Agency, the LCOE (2022 dollars) for combined cycle natural gas, solar, and land-based wind are in the range of $40-50/MWh. Lazard’s 2018 LCOE Analysis lists similar values with a wind LCOE as low as $29/MWh. Nuclear is much higher. Offshore wind is much higher. Coal is much higher.
DOE presents the case that LCOE numbers should not be compared without also taking into account the electric system value of the generation source, which evaluates the cost to generate electricity that is displaced by the new generation project. The metric is called, Levelized Avoided Cost of Electricity, or LACE, and is specific not only to the generation source, but also highly reliant on the localized grid market. As with LCOE, LACE is expressed in $/MWh. Theoretically, if the LACE for a particular generation source is higher than the LCOE, then the economics for building that plant are favorable. Note that LCOE and LACE are not what the market pays for power, but are estimated lifetime electricity generation costs.
What does this mean—PPAs, LCOE, LACE?
At a high level, if someone wants to understand where the economics of different sources of power generation are headed, historical trends are critical. Future projections are also critical—however, beware projections based on wishful thinking, political agendas, and vested interests. The trick, of course, is to tell the difference.
Before going to the projections of wind generation, a brief overview of the primary technologies for wind energy provides an understanding of fundamental obstacles and opportunities.
Two major technology aspects are power level and capacity factor. Each aspect plays a heavy role in wind generation economics. Land-based wind and offshore wind also face many obstacles, some common, many unique.
Woolnorth windfarm, Northwest Tasmania, AU, source: Abbot
Wind turbines in the 1980s were in the 50 to 100kW power level. The jump to 660kW wind turbines in the mid-1990s was exciting and thought to be risky. Would such large turbines hold up in the long term? Since then, the jump to 1.6MW, 2.5MW, and even larger turbines has met with the expected doubt and excitement. However, as the technology proves itself year after year, the inevitability of larger power levels seems fixed.
Land-based wind turbines in the U.S. bump into a potential power limit due to Federal Aviation Administration (FAA) regulations for projects that exceed 500 feet (152M). Above that height, FAA requires an aeronautical study. To date, many projects have conducted aeronautical studies. The coming years will tell whether the FAA regulation limits land-based turbine power. Likely, U.S. land-based turbines won’t attain the projected power levels of offshore turbines.
Capacity factor measures the expected annual average energy produced, divided by the annual energy produced, assuming the plant operates at rated capacity for every hour of the year.
Why is the capacity factor important?
U.S. nuclear generation fleet has a reported capacity factor of about 92%. Wind power capacity factors in the 1980s and 1990s were in the teens. For that reason, many have considered nuclear the very definition of baseload power, while most have considered wind intermittent and non-dispatchable—i.e., wind power is only available when the wind blows.
As wind’s capacity factor rises, the knock against intermittent and non-dispatchable power becomes more difficult to defend. For example, a few years ago, an excellent land-based windfarm capacity factor might have been in the mid-30s. Now, capacity factors for newly sited land-based wind farms regularly exceed 40%, with projections by DOE and others of up to 60%. For comparison, coal and natural gas generation capacity factors have been reported at 50 to 60% because of their new roles as load followers.
Logically, wind capacity factor should be heavily influenced by siting—and it is. However, technology increasingly influences it. For example, the development of lower specific power wind turbines was originally undertaken to make better use of lower wind resource regimes. However, developers now use low power density wind turbines, even in high wind resource regimes, because they can attain higher capacity factors.
When windfarm capacity factors were low, the conventional wisdom to firm wind generated electricity was to add gas-fired or coal-fired generation, MW for MW. Then, the idea was to add energy storage, typically batteries.
Wind-generated power to the grid is valuable even at lower capacity factors, which is reflected in LCOE and LACE calculations and modeling. With high capacity factors, combined with large regional grid markets (see grid integration section), who needs grid-firming? Wind may require only minimal energy storage. A National Renewable Energy Laboratories (NREL) study shows the value of windfarms for frequency regulation as an ancillary grid service.
Capacity factors will only rise because of improvements in siting decisions, larger turbines, lower specific power turbines, and other optimization methods. High capacity factors greatly improve LCOE economics as well as value to the grid.
Obstacles to Land-Based Wind
Pattern Energy’s Corona project, just approved in New Mexico, is 2.2GW. That is the power level of a good size nuclear power plant, say Pacific Gas & Electric’s Diablo Canyon or Southern Company’s Vogtle 3 & 4. Diablo Canyon, until it goes offline in 2024, will be the last nuclear power plant operating in California. Vogtle 3 & 4 could be the last conventional nuclear power plant built in the U.S.
The Corona wind plant will be the largest wind plant in the western hemisphere. One problem—the transmission line plan proposed by Sun Zia, a separate company from Pattern Energy, was recently sent back by the New Mexico Public Regulation Commission for revision. The Corona plant would be the primary user of the Sun Zia transmission project. Sun Zia sees the Corona plant approval as very positive for its effort to gain approval for the transmission project. However, the proposed transmission project has been in the works for a decade. Many issues have been resolved, but obstacles remain. Many U.S. wind projects have run squarely into transmission-limiting operations.
To say transmission is a growing pain for the land-based wind industry would be a large understatement. Transmission projects require extensive environmental impact reviews, negotiation with property owners, and lots of lead time and money.
While land-based windfarms are currently considered the lowest LCOE power generation, offshore wind is coming into its own. Dominated by European projects, offshore wind is beginning to see deployment in Asia, the U.S., and the rest of the world.
Danish Windfarm, Near Copenhagen, source: Abbot
Most major wind turbine manufacturers have 8MW turbines available, with 12MW in the near-future deployment stage. For example, General Electric (GE) has announced its 12MW Haliade-X turbine for deployment in the 2021 timeframe.
A consortium led by the University of Virginia, with funding provided by the Advanced Research Projects Agency—Energy (ARPA-E, DOE), is developing a 50MW wind turbine design. The consortium includes NREL, Sandia National Laboratories, the University Illinois, the University of Colorado, and the Colorado School of Mines. Corporate advisors are Vestas Wind Systems, Siemens AG, GE, and Dominion Resources. One blade design basis comes from Sandia Lab’s Segmented Ultralight Morphing Rotor (SUMR) technology. The design goal is to reduce the LCOE for offshore wind by 50% by 2025.
Concept of SUMR project. Source: Chao Qin
The Hywind floating offshore windfarm reported a capacity factor of 65.1% during November 2017 through January 2018. Equinor (the Norwegian company formerly known as Statoil) owns the 30MW plant, which began operations in late 2017. It comprises five Siemens 6MW floating wind turbines.
The GE 12MW Haliade wind turbine has a projected capacity factor of 63%. As offshore wind turbine hub heights increase, the blades reach into a wind regime that blows more steadily, which increases the capacity factor.
Offshore wind also typically produces power coincident with peak onshore power demand, which greatly increases the value to the grid, and thus improves the LACE calculations. A recent Lawrence Berkeley National Laboratories study noted that the relative value of East Coast offshore wind to the grid could be $20 to $40/MW higher than land-based wind due to shorter distance to load and coincident power production.
Obstacles to Offshore Wind
Land-based wind has it easy compared with offshore wind obstacles. A wind farm in New Mexico will rarely face a hurricane, or earthquake, or moving ice on a frozen lake, or worry about the infrastructure for construction and installation of a floating platform, or have to consider the politics of shipping turbine components just to comply with an obscure cabotage act.
Cabotage? The Jones Act. The Merchant Marine Act of 1920 was enacted to require vessels carrying merchandise between two U.S. ports (or points) that they must be U.S.-flagged, -owned (75%), -built (75%), and predominantly crewed by U.S. citizens. Many studies analyzing the economic impact of the Jones Act, including one by the U.S. International Trade Commission, show a net cost of $1-2B annually to U.S. consumers. And so it is with offshore wind developers when they transport turbine components for construction. Very few ships conform with Jones Act requirements, and those that do are prohibitively expensive to own and operate. Building Jones Act vessels is one solution, albeit lengthy and expensive. While lobbying and other measures have found limited success, floating platforms and going further out to sea may help.
Typhoons in the Pacific and hurricanes in the Atlantic are an ever present threat to ships, coastal communities, and now wind turbines. Wind turbine manufacturers MHI Vestas, Siemens Gamesa, and GE have all announced T-class, T for Typhoon, wind turbines in development in the 4MW to 8MW power levels. Considering the force of North Sea storms, and the windfarms in their path, the wind industry has abundant experience developing sturdy turbines—and failures from which to learn. As turbines grow in size, the design criteria become that much more critical. The University of Virginia 50MW design reportedly uses blade design inspired by the adaptability of palm trees’ fronds and trunks.
Offshore wind is predictable and strong. The further offshore, the greater the resource, and the less the aesthetic objection. However, the transmission line is longer, and the water may be deeper. Nobody said it would be easy. If it can be proven economical, the holy grail of wind power is the vast resource that can be conquered only using floating platform technology. A few years ago, offshore wind was considered far too expensive, maybe forever. And floating platforms were, well, nuts. The Hywind project has proven both notions wrong, and in an unthinkable timeframe. Today, hundreds of MWs of floating offshore wind commercial demonstration projects are in planning, development and construction, including a 25MW project to be deployed off of Portugal in 2019. This project will feature the WindFloat technology, developed by the California company Principle Power, Inc. GW’s of commercial floating projects, in early development stages, have been announced. The recent Lawrence Berkeley National Laboratory study projects that floating platform costs should approach and possibly be lower than fixed foundation offshore turbines. Floating platform technology is well-proven. As with land-based wind, costs will dive as supply chains are established and gain volume. 0.5GW and 1GW floating platform projects announced off Japan and Korea may be the opening of Asia to a new era of offshore wind power.
Source: Principle Power
The Grid in Transition – The Energy Imbalance Market, Energy Storage, and EVs
Market improvements such as the energy imbalance market (EIM), which is a cooperative effort between the Balancing Authorities (BAs) in the U.S. Western Interconnection can greatly enable the penetration of renewables. The California Independent System Operator (CAISO) is the largest BA and created the EIM to minimize curtailment of renewables. The EIM allows greater operational reliability and increased diversity of power generation over a vast geographical region.
A more ambitious goal is to beef up the connection between the three U.S. electricity grids: the Western Interconnection, the Eastern Interconnection, and the Electric Reliability Council of Texas. The “Interconnection Seams Study” shows that a more integrated U.S. grid system would greatly increase use of renewables and natural gas generation. Europe and China are reportedly also pursuing such an integrated grid scheme.
Energy storage is an expensive solution to solar and wind penetration. However, utilities are in the planning and implementation stages of using electric vehicles for grid services and energy storage. This type of energy storage resource comes inexpensively compared with grid level battery storage and is already in deployment with Southern California Edison’s Charge Ready program, San Diego Gas & Electric’s Power Your Drive program, and Pacific Gas and Electric’s Charge Network program. Smart workplace charging can efficiently integrate afternoon solar generation, and smart night time charging can efficiently integrate wind generation. Frequency response and demand response are other ancillary grid services that EVs can provide via unidirectional smart charging.
As the grid moves away from traditional large centralized power plants to decentralized renewables generation, most utilities and grid operators expect resiliency and reliability to improve as well.
Issues with Wind – the Public
Many local groups find windfarms objectionable. The objections include: bird kill, iceballs, aesthetics, intrusion into fishing territory, noise, worry over ratepayer impact, and assorted other issues. Historically, one of the most significant objections has been bird kill. Significantly, the National Audubon Society’s position on wind power is positive…with the proviso that windfarms must be properly sited. Their reasoning is that yes, windfarms kill birds, but the threat to birds from climate change far exceeds the threat from windfarms, and that windfarms combat climate change, which results in a net benefit.
Many studies describe the aesthetic and other objections local residents have with windfarms. With the growing momentum of land-based and offshore windfarm development, however, permitting and project approvals become ever more perfunctory. This is especially true as local governments see the importance of jobs and revenue to the community.
The Politics of Renewables
Jobs and tax revenue. Largely, advancement of renewables is a bipartisan win. However, the reason for this is economic, not environmental. Bringing climate change into the discussion instantly alienates a major segment of the population. Not so when the discussion shifts to jobs. In the U.S., both Republicans and Democrats tout the gain in jobs related to renewable energy. The Bureau of Labor Statistics lists solar panel installers and wind turbine technicians as the two fastest growing occupations in the U.S. In Massachusetts, the Bedford Marine Commerce Terminal, designed to support development of offshore wind projects, is estimated to bring over 7,000 jobs and over a $1B to the local economy over the next ten years.
The U.S. Energy and Employment Report compiled by the Department of Energy, published January 2018, lists jobs associated with Solar at 373,807 and Wind at 101,738. These numbers have grown rapidly over the years. The U.S. jobs associated with Coal (generation and mining combined) are approximately 160,000 and decreasing yearly due to the accelerating retirements of coal plants and plateauing demand of coal worldwide. U.S. coastal states—New York, New Jersey, Rhode Island, Massachusetts, California, and others—are jumping on the jobs potential of offshore wind. The projected jobs and economic growth are staggering based on the potential resource of multi-TW for coastal U.S.
Subsidies are also a point of contention. Some proponents of wind and many of those skeptical of wind have seized on wind industry’s Production Tax Credit (PTC) phaseout as doom and gloom for the future of wind generation. A more reasoned analysis suggests that while the PTC has certainly assisted with deployment of wind projects, the PTC phaseout may not have a major impact. The reason is the rapid decrease in LCOE for all the reasons listed above. Subsidy-free wind power appears on the horizon for offshore wind with German and Swedish projects slated to soon come on line estimated at $38/MWh.
Global Energy Market Projections – Why Wind Will Dominate
Global wind power currently accounts for a small percentage of total power production. In the U.S., however, wind power MWh production is on pace to pass hydro in 2018. What about solar? The race is tightening. MWs of solar are growing faster than wind and could catch up by 2023, when each approach 1 terawatt (TW) of generation capacity. Of course, not all terawatts are created equal. The capacity factor of utility-scale solar PV is on the order of 30-35%. In context, this lower capacity factor is generally not as valuable as wind’s high capacity factor relative to the dispatchability and intermittency argument, as well as general value to grid.
Coal, nuclear, and natural gas will have their significant near-term market share, but the long-term outlook is dim for all three. The International Energy Agency (IEA) estimates the 2018 subsidy level for fossil fuels (coal, oil, gas) is approximately $300B. How long can that last?
Floating offshore wind has very large long-term potential. Estimates are 1.9TW off the coast of UK, 2.9TW off the coast of France, 3.5TW off Japan, and another 2.5TW off the coasts of the U.S. This level of power is staggering, but is even more impressive when capacity factors in the 60-70% range, and coincident power are considered. The global potential for offshore wind is estimated at approximately 40-50TW. To take advantage of that level of resource, the obstacles to deploy offshore wind are imposing—supply chain, hurricanes/typhoons, floating platform technology, economics – but more and more, large industrial and global energy players are making the bet they can and will be overcome.
In the U.S. and many other parts of the world, coal and nuclear are in decline. Natural gas is considered to be the “bridge fuel” to the long-term build-out of renewables. Many view the goal of 100% renewable power production—wind, solar, hydro, biomass, geothermal—as only a matter of time, perhaps attainable by the 2050 to 2060 timeframe in many regions. Wind and solar lead the charge and already have low LCOE values, on a par with combined cycle natural gas.
In the long-term, wind’s high capacity factors, both land-based and offshore, combined with the drop in installation and O&M costs, make the prospects for wind as our largest future generation source, a good possibility. The answer is blowing…
Power Generation Economics
1. National Renewable Technology Laboratory, 2018 Annual Technology Baseline: Offshore Wind. https://atb.nrel.gov/electricity/2018/.
2. National Renewable Technology Laboratory, 2018 Annual Technology Baseline: Land-Based Wind. https://atb.nrel.gov/electricity/2018/.
3. Lazard, Lazard’s Levelized Cost of Energy Analysis, Version 12.0, November 2018.
4. Energy Information Agency, EIA Uses Two Simplified Metrics to Show Future Power Plant’s Relative Economics, www.eia.gov, March 29, 2018.
5. Rogers, J., A Stunningly Low Price Offshore Wind: Massachusetts Moves Forward, Union of Concerned Scientists, https://blog.ucsusa.org/john-rogers/low-price-offshore-wind-massachusetts, September 26, 2018.
6. Steggel, N. and D. Osmond, Wind Energy in Australia: Current Status and Projected Contribution to Future Electricity Supply, Windscape Institute, Windlab, 2014.
7. Merchant, E., Average US Wind Price Falls to $20 per Megawatt-Hour, njspotlight.com, August 24, 2018.
8. Energy Information Agency, Wind Generators’ Cost Declines Reflect Technology Improvements and Siting Decisions, www.eia.gov, July 12, 2018.
9. Energy Information Agency, Wind Turbine Heights and Capacities Have Increased Over the Past Decade, www.eia.gov, November 29, 2017.
10. Aho, J., L. Pao, P. Fleming, and E. Ela, “Controlling Wind Turbines for Secondary Frequency Regulation: An Analysis of AGC Capabilities under New Performance Based Compensation Policy,” National Renewable Energy Laboratory Technical Report, NREL/CP-5D00-62815, Feb. 2015. Report available at https://www.nrel.gov/docs/fy15osti/62815.pdf .
11. Wiser, R., M. Bolinger, B. Hoen, and B. Paulos, Interactive: Wind Turbines are Getting More Powerful as ‘Specific Power’ Declines, Lawrence Berkeley National Laboratory, reported on Utility Dive, August 23, 2018.
12. Gearino, D., U.S. Wind Power is ‘Going All Out’ with Bigger Tech, Falling Prices, Reports Show, www.insideclimatenews.com, August 23, 2018.
13. Paraskova, T., U.S. Wind Energy Demand Surges, Oilprice.com, May 2018.
27. Energy Information Agency, Average U.S. Construction Costs for Solar and Wind Continued to Fall in 2016, www.eia.gov, August 8, 2018.
14. Ivanova, I., Hurricane Florence Crippled Electricity and Coal -- Solar and Wind Were Back the Next Day, MoneyWatch, cbsnews.com, September 25, 2018.
15. Martin, C., On-and-Off Wind and Solar Power Pushing Coal Plants to the Brink, Bloomberg.com, October 5, 2018.
16. Climate Action Programme, World’s Most Powerful Wind Turbine Built After Donald Trump Loses Legal Battle, www.climateactionprogramme.org, April 14, 2018.
17. Roberts, D., These Huge New Wind Turbines are a Marvel. They’re Also the Future. www.vox.com, March 8, 2018.
18. Buchsbaum, L., Offshore Wind Has Taken Off in Europe, Power, www.powermag.com, May 2018.
19. Paulos, B., Offshore Wind May Finally Be Here (Really), Power, www.powermag.com, May 2018.
20. Wiser, R. and M. Bolinger, 2017 Wind Technologies Market Report, U.S. Department of Energy, Office of Energy Efficiency & Renewable Energy, http://www.osti.gov/scitech. 2017.
21. Gheorghiu, I., Breaking into the US Energy Market, Offshore Wind Developers Strive to Please All, utilitydive.com, August 9, 2018.
22. Trabish, H., High Values Are Blowing in Offshore Winds; Policymakers May Need More, utilitydive.com, May 15, 2018.
23. Johnson, T., Wind Power in New Jersey: How Big and How Soon, njspotlight.com, August 17, 2018.
24. McGraw, D., Can Offshore Wind Turbines Succeed in the Great Lakes?, scientificamerican.com, August 14, 2018.
25. Logan, A., US Offshore Enters Gigawatt-Scale Phase, But Challenges Remain, rechargenews.com, June 22, 2018.
26. Sohn, J. and D. Lewkowicz, How the Offshore Wind Energy Industry Can Overcome the Jones Act, Power, www.powermag.com, March 2018.
27. Lackner, M. and E. Baker, Why the Offshore Wind Industry is About to Take Off, https://theconversation.com, May 15, 2018.
28. Lillian, B., Deepwater Launches Major Scientific Endeavor Prep for More Offshore Wind, North American Windpower, nawindpower.com, September 26, 2018.
29. Utilities Middle East, Middle East Staff, IRENA Sees Great Potential for Offshore Wind, September 26, 2018.
30. U.S. International Trade Commission, 1999. The Economic Effects of Significant U.S. Import Restraints, Second Update 1999, Investigation No. 332-325, Publication 3201, May 1999.
31. Botsford, C. and R. Sahu, The Jones Act Contribution to Global Warming, Acid Rain and Toxic Air Contaminants, Air and Waste Management Association Conference, Paper No. 699, June 2001.
32. Dvorak, M., etal., U.S. East Coast Offshore Wind Energy Resources and Their Relationship to Peak-Time Electricity, Wind Energy, 16:977-997, 2013.
The Grid in Transition
33. Larson, A., How Does the Western Energy Imbalance Market Work?, Power, www.powermag.com, October 2018.
34. California Independent System Operator, Western Imbalance Benefits Report, July 31, 2017.
35. Brooks, A., Vehicle Charging as a Source of Grid Frequency Regulation. EVS27, Barcelona, Spain. November 2013.
36. Larson, A., It’s Time for a Macro-Grid Overlay in the U.S., Power, www.powermag.com, September 2018.
37. Patel, S., A Wind Experiment: The Hornsdale Wind Farm, Power, www.powermag.com, September 2018.
Issues with Wind
38. Firestone, J., B. Hoen and J. Rand, Are Public Objections to Wind Farms Overblown?, https://theconversation.com, May 2, 2018.
39. Geuss, M., Energy Departmnet Proposes Funding for Ohio’s First Offshore Wind Project, arstechnica.com, October 6, 2018.
40. Gheorghiu, I., Orsted Expands US Offshore Wind Presence with $510M Buy, UtilityDive.com, October 9, 2018.
41. Hill, J., New Mexico Approves Pattern Energy’s 2.2 Gigawatt Corona Wind Projects Plan, cleantechnica.com, October 5, 2018.
42. Maloney, P., DOE Energy Storage Grants Look to the Day When Renewables Rule the Grid, utilitydive.com, October 9, 2018.
43. National Audubon Society, Position on Wind, www.audubon.org, accessed October 10, 2018.
The Politics of Renewables
44. Department of Energy, U.S. Energy and Employment Report, https://usenergyjobs.org, January 2018.
45. DiChristopher, T. and J. Schoen, Trump Says 'The Coal Industry is Back.' The Government's Jobs numbers say otherwise, cnbc.com, August 23, 2018.
46. Weissman, G., R. Cross, and R. Sargent, Wind Power to Spare, The Enormous Energy Potential of Atlantic Offshore Wind, Frontier Group, March 2018.
47. Trabish, H., Developers See Value in California Offshore Wind Development, utilitydive.com, September 10, 2018.
48. Knauf, V., 5 Factors That Will Cushion the PTC Phaseout for US Wind, greentechmedia.com, August 8, 2018.
49. Miller, K., LePage’s Secretive Wind Energy Commission Appears Near Collapse, presshearld.com, September 24, 2018.
Global Energy Market Projections
50. Bade, G., Massachusets Utilities File US-Record Offshore Wind Contracts at $65/MWh, utilitydive.com, August 2, 2018.
51. Energy Information Agency, Nearly Half of Utility-Scale Capacity Installed in 2017 Came From Renewables, www.eia.gov, January 10, 2018.
52. Chestney, N., Global Wind Capacity to Rise by More Than Half in Next Five Years, Reuters, April 25, 2018.
53. Energy Information Agency, Wind Expected to Surpass Hydro as Largest Renewable Electricity Generation Source, www.eia.gov, January 24, 2018.
54. Energy Information Agency, Solar Plants Typically Install More Panel Capacity relative to their Inverter Capacity, www.eia.gov, March 16, 2018.
55. National Renewable Technology Laboratory, 2018 Annual Technology Baseline: Utility-Scale PV. https://atb.nrel.gov/electricity/2018/.
56. National Renewable Technology Laboratory, 2018 Annual Technology Baseline: Residential PV Systems. https://atb.nrel.gov/electricity/2018/.
57. Foxwell, D., IEA Chief Predicts Potential 350-GW Market for Offshore Wind, Offshore Wind Journal, owjonline.com, September 25, 2018.
58. Geuss, M., International Energy Agency Predicts Wind Will Dominate Europe’s Grid by 2027, Arstechnica.com, September 28, 2018.
59. Matsumura, W, and Z. Adam, Hard-Earned Reforms to Fossil Fuel Subsidies Are Coming Under Threat, World Energy Outlook, International Energy Agency, October 29, 2018.
60. Buchsbaum, L., Floating Offshore Wind Farms Exploit a Great Energy Resource, Power, www.powermag.com, August 2018.