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Energy Economics And Policy
Term Paper
An economic assessment of offshore wind power generation
in Norway – reaching grid parity?
Magnus Solli Haukaas
ETH Zürich
Spring 2011
Term Paper
Prof. Thomas F. Rutherford
Energy Economics And Policy
Term Paper
Abstract
Generation of offshore wind power in Norway could make the
restructuring from oil and gas services more fluent. The potential for the
renewable energy source has been known for a long time, but the problem
is that other energy sources are more profitable. The scope of the model is
to investigate the year when offshore wind energy is able to compete
economically with other energy sources. Information about the future
energy prices and the cost of production were collected. Two scenarios
were interpreted; the first scenario didn`t include subsidies from the
government, while the second scenario included the subsidies. The
calculations show that scenario 1 and scenario 2 would respectively reach
its market equilibrium around 2030 and 2023. Further, the implications of
the result is that Norway should incrementally start to develop a business
for offshore wind power generation and use the resources from the oil and
gas industry in a way that can give a comparative advantage in the future.
Energy Economics And Policy
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Contents
1 A change of direction – the use of Offshore Wind Energy 2
1.1 Increasing energy demand globally ................................................................................... 2
1.2 Exploration of energy sources in Norway.......................................................................... 2
1.3 Offshore Wind Energy in Norway ...................................................................................... 2
2 Peak oil at the Norwegian Shelf 3
2.1 Impact of the oil in the Norwegian society ....................................................................... 3
2.2 Interpretation of Hubbert`s Production Curve .................................................................. 4
3 Wind energy production estimates 4
3.1 Advantages for offshore wind power generation ............................................................. 4
3.2 HyWind – a windmill project at the south-west coast of Norway .................................... 5
3.3 Production estimates in the North Sea ............................................................................. 5
4 The economic models of Wind Energy 6
4.1 Levelised electricity generation costs................................................................................ 6
4.2 Grid Parity and its implications.......................................................................................... 7
5 The model – reaching grid parity 8
5.1 Assumptions for the model ............................................................................................... 8
5.2 Reaching grid parity by 2023 ............................................................................................. 8
5.3 Investigating cost components of a offshore windmill project ....................................... 10
5.4 Limitations of the model ................................................................................................. 12
6 Priority areas for further development 13
7 Concluding remarks 15
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List of figures
Figure 2.1: History of oil reserves and production in Norway ........................................................ 3
Figure 2.2: Hubbert´s curve for oil production in Norway .............................................................. 4
Figure 3: Windmap Norway ............................................................................................................ 5
Figure 4.1: Explanation of electricity generation costs ................................................................... 6
Figure 4.2: Load-dispatch curve for the electricity market. ............................................................ 7
Formel 5.1: Formula describing the offshore wind power`s grid parity. ........................................ 8
Figure 5.1: Graphical presentation of the two scenarios. ............................................................. 10
Figure 5.2: Cost ratios of components in a windmill project. ....................................................... 11
Figure 6.1: Graphical presentation of the weekly variation of hydro inflow and wind power
generation. .................................................................................................................................... 13
Figure 6.2: Technical information about Statoil`s HyWind – project. ........................................... 14
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1. A change of direction – the use of Offshore Wind Energy
1.1 Increasing energy demand globally
Nowadays there is a lot of discussion about peak oil. Several models are made to estimate the
time for peak oil. Whether peak oil has been reached or soon will be reached aren’t fully
understood. There are also an extensive use of carbon intensive energy sources such as coal and
gas. In addition are nuclear power plants a non-desirable energy sources due to the
environmental damage it can cause. The demand for energy is increasing, and there is often a
positive correlation between one country`s thrive to increase GDP and it`s need for energy. New
emerging markets, such as Asia, have a substantial need for energy in the future. Governments
and companies are therefore agreeing that we need a change from the present use of energy.
Renewable energy is a natural solution.
1.2 Exploration of energy sources in Norway
The discovery of oil in Norway changed the whole nation. New jobs were created, and the oil
made the fundament for the Norwegian welfare society. Reports show, however, that peak oil
has been reached. New energy sources need to be explored if Norway still expects to be an
energy-exporting country. The most important energy source in Norway is hydropower, but the
well-known energy source from waterfalls and dams has been well exploited. New research
investigates the possibilities for other renewable energy sources such as wind, sea and solar
energy.
1.3 Offshore Wind Energy in Norway
The potential for wind offshore energy has been explored in a large scale the last 30 years. After
the international oil crisis at the beginning of the 1970s the development of modern wind
generators escalated. The long coastline of Norway and the North Sea gives opportunities that
few other countries have. Statoil, the Norwegian energy company which is the largest operator
on the Norwegian continental shelf, has developed a floating wind-turbine foundation called
HyWind. Also other companies, which earlier were engaged in shipping or oil/gas industry, now
see the possibilities for entering the wind energy market. The problem is not the technology
opportunities, but rather the cost associated with the investment. It is not desirable to be a first
mover in an industry that, right now, is not giving return on the investments.
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History of Oil Reserves & Production in Norway
Production (in thousand barrels daily)
Proven Reserves (in million barrels)
A debate is ongoing in Norway. The question is whether to invest in wind energy now or to wait
until offshore wind power have been less costly. Most of the debaters agree that the investment
cost is high. Independently of the high cost, some people mean that investments at present time
will give Norway a comparative advantage in the future. The paper will investigate the cost of
offshore wind generation and the future energy prices. It will also be predicted an optimal time
for investments. In the end there will be an outlook at desirable priority areas in the years to
come.
2 Peak oil at the Norwegian Shelf
2.1 Impact of the oil in the Norwegian society
The first oil-findings in Norway are officially dated to 1969. Since then has it been activity in the
North-Sea. As of June, 10, 2010, Hegnar listed on its website that 200 000 Norwegians have jobs
that are closely related to the oil-sector. In addition, money from the “the government pension
fund of Norway” has generated new jobs in the public sector. The pension fund is almost solely
financed by profits from the offshore-industry. The oil is undebatable of great importance.
Figure 2.1 shows, according to the Statistical Review of World Energy 2010 at BP online, a
decreasing development of oil production and proven reserves.
Figure 2.1: History of oil reserves and production in Norway
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2.2 Interpretation of Hubbert`s Production Curve
Hubbert´s production curve for Norway (figure 2.2) estimates peak oil to have occurred in 2001.
The assumption for the model is that oil-production is determined by geology. New oil
recoveries in the North of Norway will most likely shift the curve upwards. Independently of
new recoveries; the amount of oil in the North Sea has declined and the source is not
inexhaustible. Therefore, the oil- and gas industry need to consider a restructuring. Offshore
Wind power generation could make the structural change frictionless. After 40 years with oil
exploration has Norway world-leading competence in the subsea industry. The expertise could
be used in developing wind turbines and grid connections in high depth water.
3 Wind energy production estimates
3.1 Advantages for offshore wind power generation
Wind power is not a recently discovered energy source. Historically have Norwegians used it for
automation in agriculture, pumping of water and electricity generation in remote areas.
According to Havvind (2010) are the advantages of offshore wind energy in Norway the
relatively stable wind conditions, large available areas and less property rights disputes
compared to onshore wind energy. Wind power does not generate pollution or other
radioactive waste. Figure (3) gives a graphical presentation of the wind potential at the coast of
Norway. In the southern parts of Norway we experience a wind speed of approximately 10 m/s.
Figure 2.2: Hubbert´s curve for oil production in Norway, Source: Raminagrobis(2007)
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Figure 3: Windmap Norway, Source: Vindteknikk.no.
3.2 HyWind – a windmill project at the south-west coast of Norway
HyWind , which was introduced earlier, is a floating windmill that operates in deep-water
environments up to 700 meters. The prototype is anchored offshore Karmøy which is at the
south-west coast of Norway. Statoil informs that the intention of the project is not to make any
revenue, but rather test how wind and waves affect the structure. After further modifications of
the windmill is it expected that it will compete in the energy markets.
3.3 Production estimates in the North Sea
According to a recent publication from Enova (2007), a Norwegian government enterprise
responsible for promotion of environmentally friendly production of energy, is the potential for
offshore wind turbines approximately 14000 TWh. The total energy consumption globally in
2010, estimated by the IEA (international energy agency, 2010), were 98000 TWh. Norway could
therefore cover a large share of the demand of energy if they utilize their resources. However,
the predictions of future offshore wind power generation have several uncertainty parameters.
Impact on natural resources is not fully understood and objections from the shipping and fish
industry makes establishment of wind parks more difficult. Further analysis of the opportunities
and restrictions will be investigated later.
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4 The economic models of Wind Energy
A purpose of the paper is to determine the costs of offshore wind energy and predict the
optimal time for investments. Two economic models will be introduced before interpreting the
analysis.
4.1 Levelised electricity generation costs
First, LEC (Levelised electricity generation costs) is an economic model for comparing energy
sources. The model includes both the costs of initial investment and continuous
operations/maintenance. A project will therefore be evaluated at its entire lifetime. In addition,
the time value of money will be accounted for by the discount factor. The units are local
currency per kilowatt-hour.1 Figure 4.1 gives an explanation of the variables in the model and
how to calculate LEC.
Figure 4.1: Explanation of electricity generation costs, source: Wikipedia.org
We should be careful with some of the variables when calculating the LEC. First, what is defined
as investment expenditures? In terms of an offshore windmill project is it natural to ask
whether transmission lines should be included. Grid connections contribute with a substantial
cost. What about the environmental damage that some of the energy sources creates? When
comparing energy sources we need to look at the assumptions behind the models. Only then
can relative reliable conclusions be made.
1 The paper will use the unit NOK/kWh. The exchange rate (NOK/CHF) is 6, 01.
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Also, a small change in the discount factor can make the net present value of a project
significantly different. Determination of the discount factor should be done by comparing values
from the industry and similar environmental analysis.
4.2 Grid Parity and its implications
Second, the other concept is grid parity. Grid parity is often defined as the point where
alternative renewable energy sources are economically efficient. It means that renewable
energy sources are equal to or below the market price. In economic terminology the market
price of electricity is reflected by the market demand and supply. A load-dispatch curve gives
the relationship between the market price and production costs for different energy sources. A
typically distribution is showed in figure 4.2.
Figure 4.2: Load-dispatch curve for the electricity market.
The baseline is defined as the production of electricity at the lowest possible cost. Electricity
produced from hydropower is often the cheapest alternative. The intention later in the paper is
to investigate where offshore wind energy is located on the supply-curve. For further research is
it important to clarify the difference between SRMC (short-run marginal cost) and LRMC (long-
run marginal cost). The SRMC is the incremental change in variable costs in the short run, while
LRMC is the incremental change of total costs in the long run. Renewable energy sources tend to
have high investment costs and therefore have a high LRMC. In opposite have renewable energy
sources low SRMCs. An analysis of the cost structure should clarify whether the LRMC or the
SRMC is examined.
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5 The model – reaching grid parity
5.1 Assumptions for the model
The following analysis uses energy prices and production costs until 2030. This is because most
valid and reliable data are from this period. Calculations of the levelised cost of electricity and
energy prices are based upon the research done by Douglas-Westwood (2010). Total costs
should be interpreted as the LRMC. The costs are determined from an offshore wind energy
project with an expected lifetime of 20 years. The discount rate is 7 % and by comparing with
other environmental analysis it seems to be a reasonable assumption. According to information
available at ENOVA`s website are 8 % a guideline for their wind projects. The foundations are
located 15 km from the shore with a water depth of 20 m.
5.2 Reaching grid parity by 2025
Investigation of the model expressed in formula (1) is the purpose of this chapter.
Formel 5.1: Formula describing the offshore wind power`s grid parity.
The point of grid parity gives also information about the optional time for investments.
The costs are determined by a “bottom up” approach. Costs from recent projects are divided in
capital expenditures (investment costs) and operational expenditures. The production of
electricity is calculated from a theoretical project. Total costs in a project that are realized today
are calculated to be 1 NOK/kWh. The average electricity prices in Norway in the 1.quarter of
2011 was reported by the SSB (2011) to be 0, 57 NOK/kWh. It should be noted that the
electricity prices in Norway are at the highest in the 1.quarter of the year. The long-run marginal
costs of offshore wind energy are therefore, right now, far from grid parity. Anyway, this was
not a surprising result. Offshore wind energy industry need some time to reduce their costs.
The Norwegian government can contribute to cost reductions. Two of the most relevant
subsidies are feed-in tariffs and green certificates. The feed-in tariff offers a fixed price for
electricity generation. ENOVA subsidies the wind energy industry with 0, 08 NOK/kWh (Kjeller
Vindteknikk, 2007). The other policy instrument, green certificates, is tradable and sold per unit
generated electricity.
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Producers of renewable energy could sell the green certificates to energy producers of coal and
oil. The Swedish certificate prices could be transferred to the Norwegian case. In the last years
the prices have been stable at a level of 0, 25 NOK/kWh (Christensen, 2010). Neither the feed-in
tariff nor the green certificates are included in cost calculations from Douglas-Westwood (2010).
It will therefore be developed two scenarios. The first scenario estimates the grid parity without
subsidies while the second scenario has included the subsidies.
Due to uncertainties in oil reserves and implemented policy instruments have future energy
prices become more difficult to predict. One of the important parameters is the price of -
quotas. As pointed earlier; the analysis will not try to make a new prediction of the energy
prices, but rather use the estimates from Douglas-Westwood (2010). In real terms are the
energy prices predicted to be 0, 68 NOK/kWh in 2030. The calculation is done by evaluating the
trading of oil, coal and gas on the world market. We take the result as a prediction for the
European and Nordic energy markets.
The cost of offshore wind energy need to decreased if it`s going to be competitive in the energy
markets. As mentioned earlier so is the offshore wind energy industry relatively small, and it is
expected that it will experience cost reductions in the forthcoming years. By 2030 the levelised
production costs of offshore wind energy is estimated to be at a level of 0, 7 NOK/ kWh. Again,
this is not included feed-in tariffs and green certificates.
Figure 5.1 shows graphically the results for the two scenarios. It is taken into account that
subsidies tend to decrease over time. This happens when offshore wind energy becomes more
profitable. The second scenario is therefore calculated with higher subsidies the next couple of
years.
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Figure 5.1: Graphical presentation of the two scenarios. First scenario is without subsidies, while the second scenario has included the subsidies.
In scenario 1 the grid parity will be reached around 2030, while scenario 2 predicts the grid
parity to be reached in 2023. The interpretation is that offshore wind energy is not profitable
before 2023(given that subsidies and green quotas are maintained). Further, most commercial
projects take 8 – 10 years to reach final construction. In addition expects EWEA, the European
wind energy association, that the transnational grid will be sufficient developed by 2020 (EWEA,
2009). The grid will contribute to a well-functioning European energy market that will benefit all
consumers. It is planned to be build first and foremost around the areas of the North Sea and
the Baltic Sea. Finally, by considering all the facts, we can expect large-scale investments by the
industry around 2020.
0
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Energy Prices
LEC
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Energy Prices
LEC with subsidies
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5.3 Investigating cost components of a offshore windmill project
To reach the estimated grid parity by 2023 the total costs need to be decreased. A sensitivity
analysis investigates the variables that contribute to the cost reduction. Figure 5.2 illustrate the
cost ratios of the most important variables. The wind turbine, electrical infrastructure and the
equipment have most significant impact on total cost.
Figure 5.2: Cost ratios of components in a windmill project.
The tower and the blades have the largest contributions to the price in large wind turbines.
Common for both the components are that the weight is crucial for cost reductions. Lower
weight of the blades minimizes the load on other components and increases the efficiency of
the turbine. In addition is the tower dependent on low steel prices. Because of the recent years
constrained supply of steel and high demand, the cost of the tower has been pushed higher.
However, by using carbon fibers, experiments show that the cost and the total weight of blades
can be reduced respectively by 14 % and 38 %. Both the two components electrical
infrastructure and equipment need considerable improvements in research & development.
Earlier have wind turbines and foundations been of most interest in R&D, but other components
of a windmill project have now been targeted.
Wind turbine
Foundations
Electrical Infrastructure
Installation
Planning & Development
Equipment
Grid maintenance & Lease
Personnel Access
Labour
Installation/Repair Vessels
Intermittency cost
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5.4 Limitations of the model
The model estimates the grid parity for offshore wind energy to encounter within the next 20
years. Compared to present cost it may look too optimistic.
The learning curve for the industry is dependent on political willingness. Research and
development is crucial to reach the desirable costs. R&D experience substantial costs. For
companies is this cost highly uncertain, and there are other markets that are more profitable
than the offshore wind energy industry. A survey that KPMG (2011) conducted shows that 76
per cent of the respondents admitted that the risk, right now, is too high. Other renewable
energy sources, such as onshore wind power, generate a larger return and have also a much
lower risk profile.
Further, compared to 5 years ago, the term risk has a deeper impact in investment analysis. The
financial crisis made companies and governments more risk-averse and the uncertainty among
market participants is still high. Douglas-Westwood (2010) does mention the impact of the
financial crisis, but it assumes that the world would recover within the next two-three years. The
length and the impact of the financial crisis could shift the grid parity substantial. As an
extension, the discount rate used in the model is not high enough compared to the criteria’s
from the industry.
The perspective of the cost analysis has been more in terms of business economics rather than
social economics. Benefits, when changing from coal-fired plant to renewable energy, are not
evaluated. Examples are -reductions (global level) and cost reductions in form of avoided
carbon taxes (local level). Other negative externalities could be a considerable loss in tourism,
fishing and shipping industry and a decrease of ecosystems.
The model assumes a project which is established in shallow water with a fixed platform. The
steep-walled fjords in Norway give problems for such foundations. Floating offshore wind plants
proves higher transmission costs. Denmark, as a comparison, has a comparative advantage in
shallow depth wind power generation.
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Variations in production and storage of wind power are another cost of importance. Two
methods are particular of interest when solving the problem. The first method uses the excess
electricity to pump water into a magazine, while the second method compresses air (CAES –
Compressed Air Energy Storage). Those costs are not fully understood in the implementation of
offshore wind energy in Norway.
In addition, steel prices could encounter fluctuations in price level which can give severe
implications for the total cost of a windmill project.
6. Priority areas for further development
By consideration of the model it seems reasonable
to invest in offshore wind power within the next 10 years.
However, an incremental change of the supply of wind
power is, right now, the best strategy. Norway has already
a clean and sustainable power generation in terms of the
production of hydropower. Hydropower has long been
viewed as a perfect fit for wind generation, providing balances
and reserves in an optimal mix. The integrated system exploits
the storage capacity of hydro power. Figure 6.1 shows the
variations in hydro inflow and wind power generation in
the Nordic countries. Hydropower can be a supplement in those periods where wind energy fails
to meet demand. For internal demand is onshore wind power and hydro power more cost
efficient. Offshore wind energy could be used in the energy market to facilitate green quotas in
neighboring countries.
Further, the government in Norway needs to establish compensation regulations that make the
industry profitable. UK is often used an example. They are considered to have the most financial
attractive regulations, and have developed to be one of the world-leading countries in the field
of offshore wind energy. Norway could share experiences with countries such as UK, Germany
and Denmark.
Figure 6.1: Graphical presentation of the weekly variation of hydro inflow and wind power generation.
Source: Holttinen(2007)
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Research of floating fundaments should
be maintained and the projects need to
be supported by the government.
Statoil´s project HyWind(figure 6.2) was
subsidized with 59 MNOK from ENOVA.
Total cost of the project was 400 MNOK.
The two-year testing period was recently
completed and the experiment has
shown positive results. New projects are
planned at the coast of Maine and
Scotland. They are expected to be
operative in approximately 5 – 6 years.
It is reported that the new windmills
have substantially reduced the costs due
to steel-reductions in the construction
(Statoil, 2010).
The Norwegian oil- and energy minister stated in March 2011 that offshore wind energy is too
costly and that the main opportunity for Norway is primarily technology development. The
expertise in subsea-technology gives Norway an advantage, and makes the structural change to
offshore wind power generation less costly. Asia, among others, is considered as a future
market. After the catastrophic tsunami event in Japan will there be a larger demand for
renewable energy sources. Also China, with its emerging market and long coastline, has an
extensive demand of energy in the future. It should be mentioned that the threat for typhoons
and other severe events are limiting factors for development of offshore windmills in Asia.
Figure 6.2: Technical information about Statoil`s HyWind – project. Source: Statoil (2010).
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Another idea is to use offshore windmills to supply oil-platforms with energy. This requires less
investment in grid connections, and reduces the total social cost of oil-extraction considerably.
HyWind has managed to deliver energy under tough conditions and can be used for this
purpose. Small communities, for example islands in the coastline of the Norway, could be
supplied entirely by wind power. The experiment at the island Utsira is the first full-scaled
project in the world where wind power is used in production of hydrogen (Sweco, 2011). Similar
projects could be fulfilled at other remote areas.
7 Concluding remarks
The combination of rapid growth of emerging countries and the future constrained supply of oil-
products implies higher oil price over time. These implications will turn into higher electricity
prices. The excessive demand will be supplied by renewable energy sources which gains market
shares in the expense of coal and natural gas. Norway is one of the world’s largest exporters of
oil and gas, and the industry is preparing to restructure and enter new markets. The potential
for offshore wind power generation in Norway is estimated to be 14000 TWh. A future energy
crisis could be avoided by the supply of wind energy.
Throughout the last 30 years have Norwegian companies acquired experiences in subsea and
offshore engineering. Norway could benefit from these capabilities and create markets for
deepwater and floating windmills. But, the offshore wind industry fails to show profitable
projects and the risk associated with the investment is considerably large. To exhibit cost
reductions in the years to come is there need for policy regulations that promotes the industry.
By comparing future energy prices and cost profiles the model estimates the grid parity to
encounter in 2023. A prerequisite is, however, that the policy makers’ implements feed-in tariffs
and green certificates. Any calculations that predict future movements involve uncertainties. An
integrated part of understanding the model is to be aware of the parameters that could make
the most severe implications. In addition to government support are cost reductions of
windmills components, such as the turbine and the floating foundations, crucial for reaching grid
parity by 2023. Considering that most commercial projects take 8-10 years to reach, a
substantial increase in investments will occur around 2020.
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The steep-walled fjords are a disadvantage for offshore wind power generation in Norway.
Therefore, before cost-efficient floating windmills are developed, it is recommended that
Norway exploits the use of hydropower and onshore wind power in a coupled energy system.
Norway should make incremental changes and gradually enter the offshore wind market. Seen
in a long-term perspective; present market participants will experience first-mover advantages
that will pay-off in the future.
Future research should focus on floating windmills and the interdependencies between wind
energy and hydropower. Finally, cooperation between the industry, policy makers and the local
communities would promote technology innovations and establish markets that secure jobs and
industries in Norway.
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