Spelling suggestions: "subject:"feather constatations"" "subject:"feather expectatations""
11 |
Present and Future Wind Energy Resources in Western CanadaDaines, Jeffrey Thomas 17 September 2015 (has links)
Wind power presently plays a minor role in Western Canada as compared to
hydroelectric power in British Columbia and coal and natural gas thermal power generation in Alberta. However, ongoing reductions in the cost of wind power generation
facilities and the increasing costs of conventional power generation, particularly if the
cost to the environment is included, suggest that assessment of the present and future
wind field in Western Canada is of some importance.
To assess present wind power, raw hourly wind speeds and homogenized monthly
mean wind speeds from 30 stations in Western Canada were analyzed over the period
1971-2000 (past). The hourly data were adjusted using the homogenized monthly
means to attempt to compensate for differences in anemometer height from the standard
height of 10m and changes in observing equipment at stations.
A regional reanalysis product, the North American Regional Reanalysis (NARR),
and simulations conducted with the Canadian Regional Climate Model (CRCM)
driven with global reanalysis boundary forcing, were compared to the adjusted station
wind-speed time-series and probability distributions. The NARR had a better temporal
correlation with the observations, than the CRCM. We posit this is due to the NARR assimilating regional observations, whereas the
CRCM did not. The NARR was generally worse than the CRCM in reproducing the observed speed distribution, possibly due to the crude representation of the regional
topography in NARR. While the CRCM was run at both standard (45 km) and
fine (15 km) resolution, the fine grid spacing does not always provide better results:
the character of the surrounding topography appears to be an important factor for
determining the level of agreement.
Multiple simulations of the CRCM at the 45 km resolution were also driven by
two global climate models (GCMs) over the periods 1971-2000 (using only historic
emissions) and 2031-2060 (using the A2 emissions scenario). In light of the CRCM
biases relative to the observations, these simulations were calibrated using quantile-quantile matching to the adjusted station observations to obtain ensembles of 9 and
25 projected wind speed distributions for the 2031-2060 period (future) at the station
locations. Both bias correction and change factor techniques were used for calibration.
At most station locations modest increases in mean wind speed were found for most
of the projected distributions, but with a large variance.
Estimates of wind power density for the projected speed distributions were made
using a relationship between wind speed and power from a CRCM simulation for both
time periods using the 15km grid. As would be expected from the wind speed results
and the proportionality of wind power to the cube of wind speed, wind power at the
station locations is more likely than not to increase in the 2031-2060 period from the
1971-2000 period.
Relative changes in mean wind speeds at station locations were found to be insensitive
to the station observations and choice of calibration technique, suggesting
that we estimate relative change at all 45km grid points using all pairs of past/future
mean wind speeds from the CRCM simulations. Overall, our results suggest that
wind energy resources in Western Canada are reasonably likely to increase at least
modestly in the future. / Graduate / 0725 / 0608 / jtdaines@uvic.ca
|
12 |
Natural gas storage level forecasting using temperature dataSundin, Daniel January 2020 (has links)
Even though the theory of storage is historically a popular view to explain commodity futures prices, many authors focus on the oil price link. Past studies have shown an increased futures price volatility on Mondays and days when natural gas storage levels are released, which could both implicate that storage levels and temperature data are incorporated in the prices. In this thesis, the U.S. natural gas storage level change is studied as a function of the consumption and production. Consumption and production are furthered segmented and separately forecasted by modelling inverse problems that are solved by least squares regression using temperature data and timeseries analysis. The results indicate that each consumer consumption segment is highly dependent of the temperature with R2-values of above 90%. However, modelling each segment completely by time-series analysis proved to be more efficient due to lack of flexibility in the polynomials, lack of used weather stations and seasonal patterns in addition to the temperatures. Although the forecasting models could not beat analysts’ consensus estimates, these present natural gas storage level drivers and can thus be used to incorporate temperature forecasts when estimating futures prices.
|
Page generated in 0.0957 seconds