# Cost of electricity by source

(Redirected from Price per watt)

The distinct ways of electricity generation can incur significantly different costs. Calculations of these costs can be made at the point of connection to a load or to the electricity grid. The cost is typically given per kilowatt-hour or megawatt-hour. It includes the initial capital, discount rate, as well as the costs of continuous operation, fuel, and maintenance. This type of calculation assists policymakers, researchers and others to guide discussions and decision making.

The levelized cost of energy (LCOE) is a measure of a power source that allows comparison of different methods of electricity generation on a consistent basis. It is an economic assessment of the average total cost to build and operate a power-generating asset over its lifetime divided by the total energy output of the asset over that lifetime. The LCOE can also be regarded as the average minimum price at which electricity must be sold in order to break even over the lifetime of the project.

## Recent global studies

Global levelized cost of generation (US Dollars per MWh)
Source Wind Solar PV Coal Combined-cycle gas
Onshore turbine low | average Utility scale low | average Existing | new Existing | new
BNEF[1] 27 | 47 26 | 51
Lazard[2] 28 | 41 32 | 37 33 | 109 44 | 56
IRENA[3] 44 | 56 58 | 85

### BNEF (2019)

In October, 2019, Bloomerg New Energy Finance found that "the price of wind and solar power continue to fall, with offshore wind posting the most impressive cost reductions and solar PV and onshore wind now as cheap as any other source of power in California, China and parts of Europe. As a result, fossil fuel power plants are being increasingly marginalized in a number of markets, a trend that is set to continue in years to come." [1]

### Lazard (2019)

In November, 2019, Lazard found "onshore wind and utility-scale solar), which became cost-competitive with conventional generation several years ago on a new-build basis, continue to maintain competitiveness with the marginal cost of existing conventional generation technologies." [2]

### IRENA (2019)

The International Renewable Energy Agency (IRENA) released a study based on comprehensive international datasets in May 2019 which found "In most parts of the world today, renewables are the lowest-cost source of new power generation. As costs for solar and wind technologies continue falling, this will become the case in even more countries. Onshore wind and solar PV are set by 2020 to consistently offer a less expensive source of new electricity than the least-cost fossil fuel alternative, without financial assistance."[3]

## Cost factors

While calculating costs, several internal cost factors have to be considered.[4] Note the use of "costs," which is not the actual selling price, since this can be affected by a variety of factors such as subsidies and taxes:

• Capital costs (including waste disposal and decommissioning costs for nuclear energy) – tend to be low for gas and oil power stations; moderate for onshore wind turbines and solar PV (photovoltaics); higher for coal plants and higher still for waste to energy, wave and tidal, solar thermal, offshore wind and nuclear.
• Fuel costs – high for fossil fuel and biomass sources, low for nuclear, and zero for many renewables. Fuel costs can vary somewhat unpredictably over the life of the generating equipment, due to political and other factors.
• Factors such as the costs of waste (and associated issues) and different insurance costs are not included in the following: Works power, own use or parasitic load – that is, the portion of generated power actually used to run the station's pumps and fans has to be allowed for.

To evaluate the total cost of production of electricity, the streams of costs are converted to a net present value using the time value of money. These costs are all brought together using discounted cash flow.[5][6]

### Capital costs

For power generation capacity capital costs are often expressed as overnight cost per watt. Estimated costs are:

• gas/oil combined cycle power plant - $1000/kW (2019)[7] • onshore wind -$1600/kW (2019)[7]
• offshore wind - $6500/kW (2019)[7] • solar PV (fixed) -$1060/kW (utility),[8] $1800/kW (2019)[7] • solar PV (tracking)-$1130/kW (utility)[8] $2000/kW (2019)[7] • battery storage power -$2000/kW (2019)[7]
• conventional hydropower - $2680/kW (2019)[7] • geothermal -$2800/kW (2019)[7]
• coal (with SO2 and NOx controls)- $3500–3800/kW[9] • advanced nuclear -$6000/kW (2019)[7]

### France

The International Energy Agency and EDF have estimated for 2011 the following costs.[citation needed] For nuclear power, they include the costs due to new safety investments to upgrade the French nuclear plant after the Fukushima Daiichi nuclear disaster; the cost for those investments is estimated at 4 €/MWh. Concerning solar power, the estimate of 293 €/MWh is for a large plant capable of producing in the range of 50–100 GWh/year located in a favorable location (such as in Southern Europe). For a small household plant that can produce around 3 MWh/year, the cost is between 400 and 700 €/MWh, depending on location. Solar power was by far the most expensive renewable source of electricity among the technologies studied, although increasing efficiency and longer lifespan of photovoltaic panels together with reduced production costs have made this source of energy more competitive since 2011. By 2017, the cost of photovoltaic solar power had decreased to less than 50 €/MWh.

French LCOE in €/MWh (2011)
Technology Cost in 2011 Cost in 2017
Hydro power 20
Nuclear (with state-covered insurance costs) 50 50
Nuclear EPR 100[47]
Natural gas turbines without CO2 capture 61
Onshore wind 69 60[47]
Solar farms 293 43.24[48]

### Germany

Comparison of the levelized cost of electricity for some newly built renewable and fossil-fuel based power stations in EuroCent per kWh (Germany, 2018)[49]
Note: employed technologies and LCOE differ by country and change over time.

In November 2013, the Fraunhofer Institute for Solar Energy Systems ISE assessed the levelised generation costs for newly built power plants in the German electricity sector.[50] PV systems reached LCOE between 0.078 and 0.142 Euro/kWh in the third quarter of 2013, depending on the type of power plant (ground-mounted utility-scale or small rooftop solar PV) and average German insolation of 1000 to 1200 kWh/ per year (GHI). There are no LCOE-figures available for electricity generated by recently built German nuclear power plants as none have been constructed since the late 1980s. An update of the ISE study was published in March 2018.[49]

German LCOE in €/MWh
ISE (2013) ISE (2018)
Technology Low cost High cost Low cost High cost
Coal-fired power plants brown coal 38 53 46 80
hard coal 63 80 63 99
CCGT power plants 75 98 78 100
Wind power Onshore wind farms 45 107 40 82
Offshore wind farms 119 194 75 138
Solar PV systems 78 142 37 115
Biogas power plant 135 250 101 147
Source: Fraunhofer ISE (2013) – Levelized cost of electricity renewable energy technologies[50]

Source: Fraunhofer ISE (2018) – Stromgestehungskosten erneuerbare Energien[49]

### Japan

A 2010 study by the Japanese government (pre-Fukushima disaster), called the Energy White Paper,[citation needed] concluded the cost for kilowatt hour was ¥49 for solar, ¥10 to ¥14 for wind, and ¥5 or ¥6 for nuclear power.

Masayoshi Son, an advocate for renewable energy, however, has pointed out that the government estimates for nuclear power did not include the costs for reprocessing the fuel or disaster insurance liability. Son estimated that if these costs were included, the cost of nuclear power was about the same as wind power.[51][52][53]

### United Kingdom

The Institution of Engineers and Shipbuilders in Scotland commissioned a former Director of Operations of the British National Grid, Colin Gibson, to produce a report on generation levelised costs that for the first time would include some of the transmission costs as well as the generation costs. This was published in December 2011.[54] The institution seeks to encourage debate of the issue, and has taken the unusual step among compilers of such studies of publishing a spreadsheet.[55]

On 27 February 2015 Vattenfall Vindkraft AS agreed to build the Horns Rev 3 offshore wind farm at a price of 10.31 Eurocent per kWh. This has been quoted as below £100 per MWh.

In 2013 in the United Kingdom for a new-to-build nuclear power plant (Hinkley Point C: completion 2023), a feed-in tariff of £92.50/MWh (around US$142/MWh) plus compensation for inflation with a running time of 35 years was agreed.[56][57] The Department for Business, Energy and Industrial Strategy (BEIS) publishes regular estimates of the costs of different electricity generation sources, following on the estimates of the merged Department of Energy and Climate Change (DECC). Levelized cost estimates for new generation projects begun in 2015 are listed in the table below.[58] Estimated UK LCOE for projects starting in 2015, £/MWh Power generating technology Low Central High Wind Onshore 47 62 76 Offshore 90 102 115 Solar Large-scale PV (Photovoltaic) 71 80 94 Nuclear PWR (Pressurized Water Reactor)(a) 82 93 121 Biomass 85 87 88 Natural Gas Combined Cycle Gas Turbine 65 66 68 CCGT with CCS (Carbon capture and storage) 102 110 123 Open-Cycle Gas Turbine 157 162 170 Coal Advanced Supercritical Coal with Oxy-comb. CCS 124 134 153 IGCC (Integrated Gasification Combined Cycle) with CCS 137 148 171 (a) new nuclear power: guaranteed strike price of £92.50/MWh for Hinkley Point C in 2023[59][60]) ### United States #### Energy Information Administration Projected LCOE in the U.S. by 2020 (as of 2015) in dollars per MWh[61] The following data are from the Energy Information Administration's (EIA) Annual Energy Outlook released in 2015 (AEO2015). They are in dollars per megawatt-hour (2013 USD/MWh). These figures are estimates for plants going into service in 2020.[18] The LCOE below is calculated based off a 30-year recovery period using a real after tax weighted average cost of capital (WACC) of 6.1%. For carbon intensive technologies 3 percentage points are added to the WACC. (This is approximately equivalent fee of$15 per metric ton of carbon dioxide CO
2
)

Since 2010, the US Energy Information Administration (EIA) has published the Annual Energy Outlook (AEO), with yearly LCOE projections for future utility-scale facilities to be commissioned in about five years' time. In 2015, EIA has been criticized by the Advanced Energy Economy (AEE) Institute after its release of the AEO 2015-report to "consistently underestimate the growth rate of renewable energy, leading to 'misperceptions' about the performance of these resources in the marketplace". AEE points out that the average power purchase agreement (PPA) for wind power was already at $24/MWh in 2013. Likewise, PPA for utility-scale solar PV are seen at current levels of$50–$75/MWh.[62] These figures contrast strongly with EIA's estimated LCOE of$125/MWh (or $114/MWh including subsidies) for solar PV in 2020.[63] Projected LCOE in the U.S. by 2022 (as of 2016)$/MWh
Plant type Min Capacity-weighted average Max
Wind onshore 43.4 55.8 75.6
Wind offshore 136.6 NB 212.9
Solar PV 58.3 73.7 143.0
Geothermal 42.8 44.0 53.4
Hydro 57.4 63.9 69.8
Natural-gas-fired conventional combined cycle 52.4 58.6 83.2
Natural-gas-fired advanced combined cycle 51.6 53.8 81.7
Natural-gas-fired advanced CC with CCS 63.1 NB 90.4
Natural-gas-fired conventional combustion turbine 98.8 100.7 148.3
Natural-gas-fired advanced combustion turbine 85.9 87.1 129.8
Biomass 84.8 97.7 125.3
Solar thermal 176.7 NB 372.8
Coal with 30% carbon sequestration 128.9 NB 196.3
Coal with 90% carbon sequestration 102.7 NB 142.5

The electricity sources which had the most decrease in estimated costs over the period 2010 to 2019 were solar photovoltaic (down 88%), onshore wind (down 71%) and advanced natural gas combined cycle (down 49%).

For utility-scale generation put into service in 2040, the EIA estimated in 2015 that there would be further reductions in the constant-dollar cost of concentrated solar power (CSP) (down 18%), solar photovoltaic (down 15%), offshore wind (down 11%), and advanced nuclear (down 7%). The cost of onshore wind was expected to rise slightly (up 2%) by 2040, while natural gas combined cycle electricity was expected to increase 9% to 10% over the period.[63]

Historical summary of EIA's LCOE projections (2010–2019)
Estimate in $/MWh Coal convent'l Nat. gas combined cycle Nuclear advanced Wind Solar of year ref for year convent'l advanced onshore offshore PV CSP 2010 [64] 2016 100.4 83.1 79.3 119.0 149.3 191.1 396.1 256.6 2011 [65] 2016 95.1 65.1 62.2 114.0 96.1 243.7 211.0 312.2 2012 [66] 2017 97.7 66.1 63.1 111.4 96.0 N/A 152.4 242.0 2013 [67] 2018 100.1 67.1 65.6 108.4 86.6 221.5 144.3 261.5 2014 [68] 2019 95.6 66.3 64.4 96.1 80.3 204.1 130.0 243.1 2015 [63] 2020 95.1 75.2 72.6 95.2 73.6 196.9 125.3 239.7 2016 [69] 2022 NB 58.1 57.2 102.8 64.5 158.1 84.7 235.9 2017 [70] 2022 NB 58.6 53.8 96.2 55.8 NB 73.7 NB 2018 [71] 2022 NB 48.3 48.1 90.1 48.0 124.6 59.1 NB 2019 [71] 2023 NB 40.8 40.2 NB 42.8 117.9 48.8 NB Nominal change 2010–2019 NB −48% −49% NB −71% -38% −88% NB Note: Projected LCOE are adjusted for inflation and calculated on constant dollars based on two years prior to the release year of the estimate. Estimates given without any subsidies. Transmission cost for non-dispatchable sources are on average much higher. NB = "Not built" (No capacity additions are expected.) #### NREL OpenEI (2015) OpenEI, sponsored jointly by the US DOE and the National Renewable Energy Laboratory (NREL), has compiled a historical cost-of-generation database[72] covering a wide variety of generation sources. Because the data is open source it may be subject to frequent revision. LCOE from OpenEI DB as of June, 2015 Plant type (USD/MWh) Min Median Max Data source year Distributed generation 10 70 130 2014 Hydropower Conventional 30 70 100 2011 Small Hydropower 140 2011 Wind Onshore (land based) 40 80 2014 Offshore 100 200 2014 Natural gas Combined cycle 50 80 2014 Combustion turbine 140 200 2014 Coal Pulverized, scrubbed 60 150 2014 Pulverized, unscrubbed 40 2008 IGCC, gasified 100 170 2014 Solar Photovoltaic 60 110 250 2014 CSP 100 220 2014 Geothermal Hydrothermal 50 100 2011 Blind 100 2011 Enhanced 80 130 2014 Biopower 90 110 2014 Fuel cell 100 160 2014 Nuclear 90 130 2014 Ocean 230 240 250 2011 Note: Only median value = only one data point. Only max + min value = only two data points #### California Energy Commission (2014) LCOE data from the California Energy Commission report titled "Estimated Cost of New Renewable and Fossil Generation in California".[73] The model data was calculated for all three classes of developers: merchant, investor-owned utility (IOU), and publicly owned utility (POU). Type Year 2013 (nominal $$) (/MWh) Year 2024 (nominal$$) ($/MWh)
Name Merchant IOU POU Merchant IOU POU
Generation turbine 49.9 MW 662.81 2215.54 311.27 884.24 2895.90 428.20
Generation turbine 100 MW 660.52 2202.75 309.78 881.62 2880.53 426.48
Generation turbine – Advanced 200 MW 403.83 1266.91 215.53 533.17 1615.68 299.06
Combined-cycle 2CTs no duct firing 500 MW 116.51 104.54 102.32 167.46 151.88 150.07
Combined-cycle 2CTs with duct firing 500 MW 115.81 104.05 102.04 166.97 151.54 149.88
Biomass fluidized bed boiler 50 MW 122.04 141.53 123.51 153.89 178.06 156.23
Geothermal binary 30 MW 90.63 120.21 84.98 109.68 145.31 103.00
Geothermal flash 30 MW 112.48 146.72 109.47 144.03 185.85 142.43
Solar parabolic trough without storage 250 MW 168.18 228.73 167.93 156.10 209.72 156.69
Solar parabolic trough with storage 250 MW 127.40 189.12 134.81 116.90 171.34 123.92
Solar power tower without storage 100 MW 152.58 210.04 151.53 133.63 184.24 132.69
Solar power tower with storage 100 MW 6HR 145.52 217.79 153.81 132.78 196.47 140.58
Solar power tower with storage 100 MW 11HR 114.06 171.72 120.45 103.56 154.26 109.55
Solar photovoltaic (thin-film) 100 MW 111.07 170.00 121.30 81.07 119.10 88.91
Solar photovoltaic (single-axis) 100 MW 109.00 165.22 116.57 98.49 146.20 105.56
Solar photovoltaic (thin-film) 20 MW 121.31 186.51 132.42 93.11 138.54 101.99
Solar photovoltaic (single-axis) 20 MW 117.74 179.16 125.86 108.81 162.68 116.56
Wind class 3 100 MW 85.12 104.74 75.8 75.01 91.90 68.17
Wind class 4 100 MW 84.31 103.99 75.29 75.77 92.88 68.83

In November 2015, the investment bank Lazard headquartered in New York, published its ninth annual study on the current electricity production costs of photovoltaics in the US compared to conventional power generators. The best large-scale photovoltaic power plants can produce electricity at US$50 per MWh. The upper limit at US$60 per MWh. In comparison, coal-fired plants are between US$65 and$150 per MWh, nuclear power at US$97 per MWh. Small photovoltaic power plants on roofs of houses are still at 184–300 USD per MWh, but which can do without electricity transport costs. Onshore wind turbines are 32–77 USD per MWh. One drawback is the intermittency of solar and wind power. The study suggests a solution in batteries as a storage, but these are still expensive so far.[74][75] Lazard's long standing Levelized Cost of Energy (LCOE) report is widely considered and industry benchmark. In 2015 Lazard published its inaugural Levelized Cost of Storage (LCOS) report, which was developed by the investment bank Lazard in collaboration with the energy consulting firm, Enovation.[76] Below is the complete list of LCOEs by source from the investment bank Lazard.[74] Plant type (USD/MWh) Low High Energy efficiency 0 50 Wind 32 77 Solar PV – thin-film utility-scale 50 60 Solar PV – crystalline utility-scale 58 70 Solar PV – rooftop residential 184 300 Solar PV – rooftop C&I 109 193 Solar thermal with storage 119 181 Microturbine 79 89 Geothermal 82 117 Biomass direct 82 110 Fuel cell 106 167 Natural gas reciprocating engine 68 101 Gas combined cycle 52 78 Gas peaking 165 218 IGCC 96 183 Nuclear 97 136 Coal 65 150 Battery storage ** ** Diesel reciprocating engine 212 281 NOTE: ** Battery storage is no longer include in this report (2015). It has been rolled into its own separate report LCOS 1.0, developed in consultation with Enovation Partners (see charts below). Below are the LCOSs for different battery technologies. This category has traditionally been filled by diesel engines. These are "behind the meter" applications.[77] Purpose Type Low ($/MWh) High ($/MWh) MicroGrid Flow battery 429 1046 MicroGrid Lead-acid 433 946 MicroGrid Lithium-ion 369 562 MicroGrid Sodium 411 835 MicroGrid Zinc 319 416 Island Flow battery 593 1231 Island Lead-acid 700 1533 Island Lithium-ion 581 870 Island Sodium 663 1259 Island Zinc 523 677 Commercial and industrial Flow battery 349 1083 Commercial and industrial Lead-acid 529 1511 Commercial and industrial Lithium-ion 351 838 Commercial and industrial Sodium 444 1092 Commercial and industrial Zinc 310 452 Commercial appliance Flow battery 974 1504 Commercial appliance Lead-acid 928 2291 Commercial appliance Lithium-Ion 784 1363 Commercial appliance Zinc 661 833 Residential Flow battery 721 1657 Residential Lead-acid 1101 2238 Residential Lithium-ion 1034 1596 All of the above Traditional method Diesel reciprocating engine 212 281 Below are the LCOSs for different battery technologies. This category has traditionally been filled by natural-gas engines. These are "in front of the meter" applications.[77] Purpose Type Low ($/MWh) High ($/MWh) Transmission system Compressed air 192 192 Transmission system Flow battery 290 892 Transmission system Lead-acid 461 1429 Transmission system Lithium-ion 347 739 Transmission system Pumped hydro 188 274 Transmission system Sodium 396 1079 Transmission system Zinc 230 376 Peaker replacement Flow battery 248 927 Peaker replacement Lead-acid 419 1247 Peaker replacement Lithium-ion 321 658 Peaker replacement Sodium 365 948 Peaker replacement Zinc 221 347 Frequency regulation Flywheel 276 989 Frequency regulation Lithium-ion 211 275 Distribution services Flow battery 288 923 Distribution services Lead-acid 516 1692 Distribution services Lithium-ion 400 789 Distribution services Sodium 426 1129 Distribution services Zinc 285 426 PV integration Flow battery 373 950 PV integration Lead-acid 402 1068 PV integration Lithium-ion 355 686 PV integration Sodium 379 957 PV integration Zinc 245 345 All of the above Traditional method Gas peaker 165 218 #### Lazard (2016) On December 15, 2016 Lazard released version 10[78] of their LCOE report and version 2[79] of their LCOS report. Type Low ($/MWh) High ($/MWh) Wind 32 62 Solar PV – crystalline utility-scale 49 61 Solar PV – thin-film utility-scale 46 56 Solar PV – community 78 135 Solar PV – rooftop residential 138 222 Solar PV – rooftop C&I 88 193 Solar thermal tower with storage 119 182 Microturbine 76 89 Geothermal 79 117 Biomass direct 77 110 Fuel cell 106 167 Natural gas reciprocating engine 68 101 Gas combined cycle 48 78 Gas peaking 165 217 IGCC 94 210 Nuclear 97 136 Coal 60 143 Diesel reciprocating engine 212 281 #### Lazard (2017) On November 2, 2017 the investment bank Lazard released version 11[80] of their LCOE report and version 3[81] of their LCOS report.[82] Generation type Low ($/MWh) High ($/MWh) Wind 30 60 Solar PV – crystalline utility-scale 46 53 Solar PV – thin-film utility-scale 43 48 Solar PV – community 76 150 Solar PV – rooftop residential 187 319 Solar PV – rooftop C&I 85 194 Solar thermal tower with storage 98 181 Microturbine 59 89 Geothermal 77 117 Biomass direct 55 114 Fuel cell 106 167 Natural gas reciprocating engine 68 106 Gas combined cycle 42 78 Gas peaking 156 210 IGCC 96 231 Nuclear 112 183 Coal 60 143 Diesel reciprocating engine 197 281 Below are the unsubsidized LCOSs for different battery technologies for "behind the meter" (BTM) applications.[81] Use case Storage type Low ($/MWh) High ($/MWh) Commercial Lithium-ion 891 985 Commercial Lead-acid 1057 1154 Commercial Advanced lead 950 1107 Residential Lithium-ion 1028 1274 Residential Lead-acid 1160 1239 Residential Advanced lead 1138 1188 Below are the unsubsidized LCOSs for different battery technologies "front of the meter" (FTM) applications.[81] Use case Storage type Low ($/MWh) High ($/MWh) Peaker replacement Flow battery (V) 209 413 Peaker replacement Flow battery (Zn) 286 315 Peaker replacement Lithium-ion 282 347 Distribution Flow battery (V) 184 338 Distribution Lithium-ion 272 338 Microgrid Flow battery (V) 273 406 Microgrid Lithium-ion 383 386 Note: Flow battery value range estimates ## Renewables ### Photovoltaics European PV LCOE range projection 2010–2020 (in €-cts/kWh)[83] Price history of silicon PV cells since 1977 Photovoltaic prices have fallen from$76.67 per watt in 1977 to nearly $0.102 per watt in October 2019, for multi crystalline silicon solar cells and module price to$0.21 per watt.[84][85] This is seen as evidence supporting Swanson's law, which states that solar cell prices fall 20% for every doubling of cumulative shipments. The famous Moore's law calls for a doubling of transistor count every two years.

By 2011, the price of PV modules per MW had fallen by 60% since 2008, according to Bloomberg New Energy Finance estimates, putting solar power for the first time on a competitive footing with the retail price of electricity in some sunny countries; an alternative and consistent price decline figure of 75% from 2007 to 2012 has also been published,[86] though it is unclear whether these figures are specific to the United States or generally global. The levelised cost of electricity (LCOE) from PV is competitive with conventional electricity sources in an expanding list of geographic regions,[12] particularly when the time of generation is included, as electricity is worth more during the day than at night.[87] There has been fierce competition in the supply chain, and further improvements in the levelised cost of energy for solar lie ahead, posing a growing threat to the dominance of fossil fuel generation sources in the next few years.[88] As time progresses, renewable energy technologies generally get cheaper,[89][90] while fossil fuels generally get more expensive:

The less solar power costs, the more favorably it compares to conventional power, and the more attractive it becomes to utilities and energy users around the globe. Utility-scale solar power [could in 2011] be delivered in California at prices well below $100/MWh ($0.10/kWh) less than most other peak generators, even those running on low-cost natural gas. Lower solar module costs also stimulate demand from consumer markets where the cost of solar compares very favourably to retail electric rates.[91]

In the year 2015, First Solar agreed to supply solar power at 3.87 cents/kWh levelised price from its 100 MW Playa Solar 2 project which is far cheaper than the electricity sale price from conventional electricity generation plants.[92] From January 2015 through May 2016, records have continued to fall quickly, and solar electricity prices, which have reached levels below 3 cents/kWh, continue to fall.[93] In August 2016, Chile announced a new record low contract price to provide solar power for $29.10 per megawatt-hour (MWh).[94] In September 2016, Abu Dhabi announced a new record breaking bid price, promising to provide solar power for$24.2 per MWh[95] In October 2017, Saudi Arabia announced a further low contract price to provide solar power for $17.90 per MWh.[96] In July 2019, Portugal announced a lowest contract price of$16.54 per MWh.[97]

With a carbon price of $50/ton (which would raise the price of coal-fired power by 5c/kWh), solar PV is cost-competitive in most locations. The declining price of PV has been reflected in rapidly growing installations, totaling a worldwide cumulative capacity of 297 GW by end 2016. According to some estimates total investment in renewables for 2011 exceeded investment in carbon-based electricity generation.[98] In the case of self consumption, payback time is calculated based on how much electricity is not brought from the grid. Additionally, using PV solar power to charge DC batteries, as used in Plug-in Hybrid Electric Vehicles and Electric Vehicles, leads to greater efficiencies, but higher costs. Traditionally, DC generated electricity from solar PV must be converted to AC for buildings, at an average 10% loss during the conversion. Inverter technology is rapidly improving and current equipment has reached 99% efficiency for small scale residential,[99] while commercial scale three-phase equipment can reach well above 98% efficiency. However, an additional efficiency loss occurs in the transition back to DC for battery driven devices and vehicles, and using various interest rates and energy price changes were calculated to find present values that range from$2,060 to $8,210[needs update] (analysis from 2009, based on a panel price of$9 per watt, about 90 times the October 2019 price listed above).[100]

It is also possible to combine solar PV with other technologies to make hybrid systems, which enable more stand alone systems. The calculation of LCOEs becomes more complex, but can be done by aggregating the costs and the energy produced by each component. As for example, PV and cogen and batteries [101] while reducing energy- and electricity-related greenhouse gas emissions as compared to conventional sources.[102]

### Solar thermal

LCOE of solar thermal power with energy storage which can operate round the clock on demand, has fallen to AU$78/MWh (US$61/MWh) in August 2017.[103] Though solar thermal plants with energy storage can work as stand alone systems, combination with solar PV power can deliver further cheaper power.[104] Cheaper and dispatchable solar thermal storage power need not depend on costly or polluting coal/gas/oil/nuclear based power generation for ensuring stable grid operation.[105][106]

When a solar thermal storage plant is forced to idle due to lack of sunlight locally during cloudy days, it is possible to consume the cheap excess infirm power from solar PV, wind and hydro power plants (similar to a lesser efficient, huge capacity and low cost battery storage system) by heating the hot molten salt to higher temperature for converting the stored thermal energy in to electricity during the peak demand hours when the electricity sale price is profitable.[107][108] Biomass fuel firing can also be incorporated in solar thermal plants economically to enhance their dispatchable generation capability.[109]

### Wind power

NREL projection: the LCOE of U.S. wind power will decline by 25% from 2012 to 2030.[110]
Estimated cost per MWh for wind power in Denmark as of 2012
Current land-based wind

In the windy great plains expanse of the central United States new-construction wind power costs in 2017 are compellingly below costs of continued use of existing coal burning plants. Wind power can be contracted via a power purchase agreement at two cents per kilowatt hour while the operating costs for power generation in existing coal-burning plants remain above three cents.[111]

Current offshore wind

In 2016 the Norwegian Wind Energy Association (NORWEA) estimated the LCoE of a typical Norwegian wind farm at 44 €/MWh, assuming a weighted average cost of capital of 8% and an annual 3,500 full load hours, i.e. a capacity factor of 40%. NORWEA went on to estimate the LCoE of the 1 GW Fosen Vind onshore wind farm which is expected to be operational by 2020 to be as low as 35 €/MWh to 40 €/MWh.[112] In November 2016, Vattenfall won a tender to develop the Kriegers Flak windpark in the Baltic Sea for 49.9 €/MWh,[113] and similar levels were agreed for the Borssele offshore wind farms. As of 2016, this is the lowest projected price for electricity produced using offshore wind.

Historic levels

In 2004, wind energy cost a fifth of what it did in the 1980s, and some expected that downward trend to continue as larger multi-megawatt turbines were mass-produced.[114] As of 2012 capital costs for wind turbines are substantially lower than 2008–2010 but are still above 2002 levels.[115] A 2011 report from the American Wind Energy Association stated, "Wind's costs have dropped over the past two years, in the range of 5 to 6 cents per kilowatt-hour recently.... about 2 cents cheaper than coal-fired electricity, and more projects were financed through debt arrangements than tax equity structures last year.... winning more mainstream acceptance from Wall Street's banks.... Equipment makers can also deliver products in the same year that they are ordered instead of waiting up to three years as was the case in previous cycles.... 5,600 MW of new installed capacity is under construction in the United States, more than double the number at this point in 2010. 35% of all new power generation built in the United States since 2005 has come from wind, more than new gas and coal plants combined, as power providers are increasingly enticed to wind as a convenient hedge against unpredictable commodity price moves."[116]

This cost has additionally reduced as wind turbine technology has improved. There are now longer and lighter wind turbine blades, improvements in turbine performance and increased power generation efficiency. Also, wind project capital and maintenance costs have continued to decline.[117] For example, the wind industry in the US in 2014 was able to produce more power at lower cost by using taller wind turbines with longer blades, capturing the faster winds at higher elevations. This opened up new opportunities in Indiana, Michigan, and Ohio. The price of power from wind turbines built 90 to 120 m (300 to 400 ft) above the ground can since 2014 compete with conventional fossil fuels like coal. Prices have fallen to about 4 cents per kilowatt-hour in some cases and utilities have been increasing the amount of wind energy in their portfolio, saying it is their cheapest option.[118]

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