Title: Energy Pricing Techniques in the Electricity Market
1Energy Pricing Techniques in the Electricity
Market
- Part 4
- Application of Weather Derivatives
- Dr Harvey Stern,
- Bureau of Meteorology, Australia
2Outline of Presentation
- Background.
- An Historical Note.
- Weather-related Risk.
- The Growing Interest.
- Asia-Pacific Region.
- Some Statistics.
- Weather Derivatives Explained.
- Examples of Applications.
- Concluding Remarks.
3Background
- Weather risk is one of the biggest uncertainties
facing business. - We get droughts, floods, fire, cyclones
(hurricanes), snow ice. - Nevertheless, economic adversity is not
restricted to disaster conditions. - A mild winter ruins a skiing season, dry weather
reduces crop yields, rain shuts-down
entertainment construction.
4Background (cont.)
- The increasing interest may be explained in terms
of - A desire to meet client needs.
- A need to reduce the cost of capital.
- Cross-fertilization between various fields.
- Entry of new participants.
- Growing responsibilities of Company Directors.
- Source Prof. John Hewsons presentation to the
Weather Risk Management Association
5An Historical Note An Early Example
- In 1992, the present author explored a
methodology to assess the risk of climate
change. - Option pricing theory was used to value
instruments that might apply to temperature
fluctuations and long-term trends. - The methodology provided a tool to cost the risk
faced (both risk on a global scale, and risk on a
company specific scale). - Such securities could be used to help firms hedge
against risk related to climate change.
6Foundation of the Weather Market
- The foundation of todays financial weather
contracts is in the US power market - For the weather-sensitive end-user, not to hedge
is to gamble on the weather. - Robert S. Dischell
7Weather-related Industry Risk
- "Shares in Harvey Norman fell almost 4 per
cent yesterday as a cool summer and a warm start
to winter cut into sales growth at the furniture
and electrical retailer's outlets Investors
were expecting better and marked the shares down
3.8 per cent to a low of 3.55 - Sales at Harvey Norman were hit on two
fronts. Firstly, air conditioning sales were
weak because of the cool summer, and a warmer
than usual start to winter had dampened demand
for heating appliances. - Source The Australian of 18 April, 2002
8Weather-related Agricultural Risk
- The Australian sugar industry is facing its
fifth difficult year in a row with a drought
dashing hopes of an improved crop in Queensland,
where 95 of Australia's sugar is grown... - Whilst dry weather during the May-December
harvest period is ideal for cane, wet weather
during this time causes the mature cane to
produce more shoots and leaves, reducing its
overall sugar content. -
- (Australian Financial Review of 8 May, 2002)
9Channels for Weather Risk Transfer
- ART (Alternative Risk Transfer) is a generic
phrase used to denote various non-traditional
forms of re/insurance and techniques where risk
is transferred to the capital markets. -
- Source http//www.artemis.bm
10The Growing Interest.
- 3,937 contracts transacted in last 12 months (up
43 compared to previous year). - Notional value of over 4.3 billion dollars (up
72). - Market dominated by US (2,712 contracts), but
growth in the past year is especially so in
Europe and Asia. - Australian market accounts for 15 contracts worth
over 25 million (6 contracts worth over 2
million, previously). - Source Weather Risk Management Association
Annual Survey (2002)
11The Diversification.
- Another significant development is the
diversification of the types of contracts that
were transacted. - Temperature-related protection (for heat and
cold) continues to be the most prevalent, making
up over 82 percent of all contracts (92 last
year) - Rain-related contracts account for 6.9 (1.6
last year), snow for 2.2 (0.6 last year) and
wind for 0.4 (0.3 last year). - Source Weather Risk Management Association
Annual Survey (2002)
12Why has ART grown?
- Risk management moving up the agenda
- A need to manage uninsurable liabilities
- A need to protect against irregular income
spikes - Source Modern ART practice (Gerling Global
Financial Products)
13What is the future of ART?
- The term Alternative Risk Transfer (ART) will
soon be a misnomer. ART is fast becoming an
essential risk management tool for primary
insurers, reinsurers and non-insurance
corporations. - Source Modern ART practice (Gerling Global
Financial Products)
14The Asia-Pacific Region
- Interest in weather risk management has grown
in the Asia-Pacific Region (covering electricity,
gas, agriculture). Countries involved include - Japan
- Korea and,
- Australia/New Zealand.
- Source Weather Risk Management Association.
15Weather-linked Securities
- Weather-linked securities have prices which are
linked to the historical weather in a region. - They provide returns related to weather observed
in the region subsequent to their purchase. - They therefore may be used to help firms hedge
against weather related risk. - They also may be used to help speculators
monetise their view of likely weather patterns.
16Securitisation
- The reinsurance industry experienced several
catastrophic events during the late 1980s early
1990s. - The ensuing industry restructuring saw the
creation of new risk-management tools. - These tools included securitisation of insurance
risks (including weather-related risks). - Weather securitisation may be defined as the
conversion of the abstract concept of weather
risk into packages of securities. - These may be sold as income-yielding structured
products.
17Catastrophe Bonds
- A catastrophe (cat) bond is an exchange of
principal for periodic coupon payments wherein
the payment of the coupon and/or the return of
the principal of the bond is linked to the
occurrence of a specified catastrophic event. - The coupon is given to the investor upfront, who
posts the notional amount of the bond in an
account. - If there is an event, investors may lose a
portion of (or their entire) principal. - If there is no event, investors preserve their
principal and earn the coupon. - Source Canter Cole at http//www.cnare.com
18Catastrophe Swaps
- A catastrophe (cat) swap is an alternative
structure, but returns are still linked to the
occurrence of an event. - However, with swaps, there is no exchange of
principal. - The coupon is still given to the investor
upfront, but the structure enables investors to
invest the notional amount of the bond in a
manner of his own choosing. - Source Canter Cole at http//www.cnare.com
19Weather Derivatives Explained Clewlow et al.
(2000) describe a derivative as "a financial
product that derives its value from other more
basic variables". These products include futures,
forwards, call options, put options, and swaps.
They describe weather derivatives as being
similar "to conventional financial derivatives,
the basic difference coming from the underlying
variables that determine the payoffs", such as
temperature, precipitation, wind, Heating Degree
Days (HDDs), and Cooling Degree Days (CDDs).
20- Pricing Derivatives
- There are three approaches that may be applied to
the pricing of derivatives. - These are
- Historical simulation (applying "burn analysis")
- Direct modelling of the underlying variables
distribution (assuming, for example, that the
variable's distribution is normal) and, - Indirect modelling of the underlying variables
distribution (via a Monte Carlo technique). - Direct modelling is chosen for the current
exercise, the distribution of forecast errors
being assumed to be normal.
21Returning to the Cane Grower
- Suppose that our cane grower has experienced an
extended period of drought. - Suppose that if rain doesn't fall next month, a
substantial financial loss will be suffered. - How might our cane grower protect against
exceptionally dry weather during the coming month?
22One Approach
- One approach could be to purchase a Monthly
Rainfall Decile 4 Put Option. - Assume that our cane grower decides only to take
this action when there is already a risk of a dry
month. - That is, when the current month's Southern
Oscillation Index (SOI) is substantially
negative. - So, the example is applied only to the cases when
the current month's Southern Oscillation Index
(SOI) is in the lowest 5 of possible values,
that is, below -16.4.
23Specifying the Decile 4 Put Option
- Strike Decile 4.
- Notional 100 per Decile (lt Decile 4).
- If, at expiry, the Decile is lt Decile 4, the
seller of the option pays the buyer 100 for each
Decile lt Decile 4.
24Pricing Methodologies
- Historical simulation.
- Direct modeling of the underlying variables
distribution. - Indirect modeling of the underlying variables
distribution (via a Monte Carlo technique).
25Payoff Chart for Decile 4 Put Option
26Outcomes for Decile 4 Put Option
27Evaluating the Decile 4 Put Option
- 14.2 cases of Decile 1 yields (.142)x(4-1)x100
42.60 - 13.2 cases of Decile 2 yields (.132)x(4-2)x100
26.40 - 8.4 cases of Decile 3 yields (.084)x(4-3)x1008
.40 - The other 25 cases (Decile 4 or above) yield
nothing. - leading to a total of 77.40, which is the price
of our put option.
28Should Companies Worry?
- In the good years, companies make big profits.
- In the bad years, companies make losses.
- - Doesnt it all balance out?
- - No. it doesnt.
- Companies whose earnings fluctuate wildly receive
unsympathetic hearings from banks and potential
investors.
29Another Example
- Another example of a weather linked option is the
Cooling Degree Day (CDD) Call Option. - Total CDDs is defined as the accumulated number
of degrees the daily mean temperature is above a
base figure. - This is a measure of the requirement for cooling.
- If accumulated CDDs exceed the strike, the
seller pays the buyer a certain amount for each
CDD above the strike.
30Pay-off Chart for a CDDCall Option
31Cooling Degree Days (1855-2000)(and climate
change)
- The chart shows frequency distribution of annual
Cooling Degree Days at Melbourne using all data
32Cooling Degree Days (1971-2000)
- The chart shows frequency distribution of annual
Cooling Degree Days at Melbourne using only
recent data
33Weather Climate Forecasts
- Daily weather forecasts may be used to manage
short-term risk (e.g. pouring concrete). - Seasonal climate forecasts may be used to manage
risk associated with long-term activities (e.g.
sowing crops). - Forecasts are based on a combination of solutions
to the equations of physics, and some
statistical techniques. - With the focus upon managing risk, the forecasts
are increasingly being couched in probabilistic
terms.
34An Illustration of theImpact of Forecasts
- When very high temperatures are forecast, there
may be a rise in electricity prices. - The electricity retailer then needs to purchase
electricity (albeit at a high price). - This is because, if the forecast proves to be
correct, prices may spike to extremely high
(almost unaffordable) levels.
35Impact of Forecast Accuracy
- If the forecast proves to be an over-estimate,
however, prices will fall back. - For this reason, it is important to take into
account forecast accuracy data in determining the
risk.
36Forecast Accuracy Data The Australian Bureau of
Meteorology's Melbourne office possesses data
about the accuracy of its temperature forecasts
stretching back over 40 years. Customers
receiving weather forecasts have, recently,
become increasingly interested in the quality of
the service provided. This reflects an overall
trend in business towards implementing risk
management strategies. These strategies include
managing weather related risk. Indeed, the US
Company Aquila developed a web site that presents
several illustrations of the concept http//www.g
uaranteedweather.com
37Using Forecast Accuracy Data
- Suppose we define a 38 deg C call option
(assuming a temperature of at least 38 deg C has
been forecast). - Location Melbourne.
- Strike 38 deg C.
- Notional 100 per deg C (above 38 deg C).
- If, at expiry (tomorrow), the maximum temperature
is greater than 38 deg C, the seller of the
option pays the buyer 100 for each 1 deg C above
38 deg C.
38Pay-off Chart 38 deg C Call Option
39Determining the Price of the38 deg C Call Option
- Between 1960 and 2000, there were 114 forecasts
of at least 38 deg C. - The historical distribution of the outcomes are
examined.
40Historical Distribution of Outcomes
41Evaluating the 38 deg C Call Option (Part 1)
- 1 case of 44 deg C yields (44-38)x1x100600
- 2 cases of 43 deg C yields (43-38)x2x1001000
- 6 cases of 42 deg C yields (42-38)x6x1002400
- 13 cases of 41 deg C yields (41-38)x13x1003900
- 15 cases of 40 deg C yields (40-38)x15x1003000
- 16 cases of 39 deg C yields (39-38)x16x1001600
- cont.
42Evaluating the 38 deg C Call Option (Part 2)
- The other 61 cases, associated with a temperature
of 38 deg C or below, yield nothing. - So, the total is 12500.
- This represents an average contribution of 110
per case, which is the price of our option.
43A Financial Guarantee The guarantee described is
that the forecast will be in error by no more
than 3C. The terms of the guarantee are that the
seller of the guarantee will pay the buyer
100.00 for each 0.1C greater than 3C that the
forecast is in error. It is the purpose of the
paper to develop an approach to pricing such a
financial guarantee, and to provide it as a
technique that is available on the web.
(after Stern Dawkins, 2003)
44The Instrument The instrument is made up of a
combination of a call option and a put option
about the next day's maximum temperature at
Melbourne, the "strikes" being set respectively
3C above and below the forecast temperature.
The taker of this option combination receives
100 for each 0.1C that the observed temperature
is above or below the respective strikes. (after
Stern Dawkins, 2003)
45Forecast Errors Dawkins and Stern (2003) show
that the magnitude of the forecast errors is
largely a function of season and synoptic
pattern. Dahni (2003) describes an automated
technique for "typing" synoptic patterns.
(after Stern Dawkins, 2003)
46Forecast Errors as a Function of Season (after
Dawkins Stern, 2003)
47Forecast Errors as a Function of Synoptic
Pattern (after Dawkins Stern, 2003)
48The Approach Used
- The approach used is as follows
- The forecast verification data is stratified
according to month, and also according to the
nature of the prevailing atmospheric circulation
- cyclonicity, direction and strength of the
surface flow. - The distribution of the magnitude of forecast
errors for each month (and also for each synoptic
pattern type) is noted this distribution is
adjusted in order to take into account a
long-term downward trend in the magnitude of the
errors - The distribution of forecast errors is assumed to
be normal for each data subset, and a "fair
value" price for the option combination for each
month and each circulation type is then obtained.
- (after Stern Dawkins, 2003)
49- Example
- The example we shall use to illustrate the
methodology is a forecast produced during the
month of January, associated with a synoptic type
flow possessing the following characteristics - weak strength
- cyclonic (curvature)
- from the north-north-west.
- Over the 40-year period (1961-2000), occurrences
of such a flow across SE Australia (over all
months of the year) have been temperature
forecasts with an RMS error of 2.70C. - (after Stern Dawkins, 2003)
50Example (cont.) More recently (1991-2000), such a
flow has been accompanied by an RMS error of (a
much reduced) 2.26C. It is then assumed that the
forecast performance during the period 1991-2000
better represents what one might anticipate to be
the current level of performance, than does the
forecast performance over the 1961-2000
period. It is also assumed that the proportional
improvement in forecasting for each individual
month (January, February, March etc.) is the
same, that is, a proportional decrease in RMS
error of (2.26/2.70)(0.84) in the current
case. (after Stern Dawkins, 2003)
51Example (cont.) The monthly RMS error calculated
over the 1961-2000 period for the current
synoptic type and the current month (3.32C in
this case) is then multiplied by the ratio (0.84)
in order to achieve an estimate of the likely RMS
error for the current forecast. So, the case of a
January cyclonic weak north-north-west synoptic
flow yields (0.84x3.32)2.79C for our estimated
RMS error. It is then assumed that the errors are
normally distributed and, utilising areas under
the standard normal curve, one calculates the
expected return on the guarantee to be 410. This
procedure is then repeated for all months and for
all synoptic patterns. (after Stern Dawkins,
2003)
52- The WEB Site
- A web site is developed in order that
- potential "customers" may readily obtain a price
for the instrument and, - researchers may test its output.
- This may be viewed and tested at
- http//www.weather-climate.com/guarantee.html
- (after Stern Dawkins, 2003)
53A View of the WEB Site
54Testing the Instruments Validity
It was considered that if, over a large number of
cases, writers of the option combination do not
make either a significant profit or a significant
loss, the validity of the "fair value" price
would be demonstrated. The instrument's validity
was then tested by calculating the "fair value"
price on independent cases taken for the entire
year of 2001. However, from an analysis of all
of the year-2001 cases, it was determined that
writers of the option combination would have
received 75,574 over the year, while paying out
only 23,800. (after Stern Dawkins, 2003)
55Testing (cont.)
Nevertheless, this substantial profit (over 200
return) is not necessarily suggesting a possible
flaw in the valuation technique. On the
contrary, it may be explained in terms of the
spectacular improvement in the accuracy of
forecasts achieved during 2001 (see next
slide). One may show that had the forecasts been
of similar skill to those of previous years, the
payout would have been much closer to the monies
received. The profit achieved by the option
writers can, therefore, be explained in terms of
that increased skill. (after Stern Dawkins,
2003)
56Sharp Improvement in Forecast Accuracy in 2001
(after Dawkins Stern, 2003)
57- Comments on the Financial Guarantee
- A methodology to price a financial guarantee
about the accuracy of a forecast has been
described and demonstrated with "real" data. - It has been shown that had such a guarantee been
applied to day-1 maximum temperature forecasts
issued during 2001 for Melbourne, providers of
the guarantee would have made a substantial
profit - on account of the increased skill displayed by
the forecasts. - (after Stern Dawkins, 2003)
58Ensemble Forecasting(another approach to
measuring forecast uncertainty)
- Another approach to obtaining a measure of
forecast uncertainty, is to use ensemble weather
forecasts. - The past decade has seen the implementation of
these operational ensemble weather forecasts. - Ensemble weather forecasts are derived by
imposing a range of perturbations on the initial
analysis. - Uncertainty associated with the forecasts may be
derived by analysing the probability
distributions of the outcomes.
59Some Important Issues
- Quality of weather and climate data.
- Changes in the characteristics of observation
sites. - Security of data collection processes.
- Privatisation of weather forecasting services.
- Value of data.
- Climate change.
60Concluding Remarks
- The sophistication of weather-related risk
management products is growing. - In evaluating weather securities one needs to use
historical weather data and forecast accuracy
data, and also to take into account climate
trends. - Ensemble forecasting is a new approach to
determining forecast uncertainty.