i workshop wind globalgeo e 3tier - matt
TRANSCRIPT
How to reduce risk
Presented by:
Matthew Hendrickson, Sr. Director Of Assessment
3TIER is Focused on Understanding the Fuel
» Founded in 1999
» Headquarters in Seattle, WA
» Offices in Panama, India, and
Australia
» Focused on renewable energy
information services
39,000 MW wind energy forecasting
7,400 MW hydropower forecasting
Extensive international wind & solar resource assessment
Pre-construction services
I. Spatial mapping
II. Climate variability analysis
III. Comprehensive net report
A. Spatial
B. Climate
C. Wake
D. Other losses
E. Uncertainty
What is Numerical Weather Prediction?
Understanding of
wind characteristics
Long-term variability
assessments
(up to 50 years)
Spatial wind maps
Global
Weather
Archive
1960-present
High
Resolution
Terrain, Soil,
and Vegetation
Data
OPTIONAL:
Onsite
Observations
INPUTS WRF ANALYSIS OUTPUTS
The Value of Higher Resolution Wind Mapping
8.0
7.0
6.0
5.0
5km resolution 1.5km resolution 500m resolution
Look at the two locations marked on each map…
Sweetwater Nearby Mountain
At 5km resolution = ~7.1m/s ~7.5m/s
At 1.5km resolution = ~6.9m/s ~7.7m/s
At 500m resolution = ~6.8m/s ~8.0m/s
The Value of High Resolution Wind Mapping
8.0
7.0
6.0
5.0
5km resolution 1.5km resolution 500m resolution
90m resolution
~9.0 m/s at mountain
. . . and understand the
spatial variability of the wind
resource, better than with
simple statistical
extrapolations and/or
interpolations of on-site
observations
Avoid Wind Holes!
Options for Understanding Long-term Variability
Using Nearby 3rd Party Station Data
Measure-Correlate-Predict
(MCP)
Traditional MCP
Measure-Correlate-Predict
✪ Reference
Site
Uses a statistical relationship
between on-site obs data and a
longer ‘reference’ site to
understand the variability of the
wind resource and determine a
long-term adjustment
ws=m*wsr+b
» Reference site needs to be a consistent, long-term time
series located within a similar flow regime as the project site
» For robust results, MCP requires high correlation between
reference site and on-site, project data
» What to do if suitable long-term reference data are not
available?
Traditional MCP
Measure-Correlate-Predict
Using Synthetic Reference Data
Numerical Weather Prediction Models
Synthetic Reference Data – Using NWP Models
» Unlike MCP analysis, Numerical Weather Prediction (NWP)
models do not require off-site reference data.
» Over 50 years of historic wind resource data at hourly
resolution can be generated utilizing NWP models
» Synthetic reference data are provided at the project-site
Numerical Weather Prediction Framework
Input Output
Global Weather
Archive
1948-present
High Resolution
Terrain, Soil, and
Vegetation Data
On-Site
Observations
Numerical
Weather
Prediction Model
(NWP)
Understanding
of Wind
Characteristics
Long-Term
Variability
Assessments
Spatial
Wind Maps
NWP wind speed
Long-term mean
NWP Output – Annual-mean Variability
Observed wind speed
Operational wind speed
NWP Output – Monthly-mean Variability
Based on single year of observations, compared to 40 year analysis
Capacity F
acto
r
Validation of 3TIER NWP Time Series
Comparison Against Reanalysis
287 QC’d Tall Towers
Average R=0.53
Median R=0.55
STD R=0.19
Skill of Reanalysis Data
287 QC’d Tall Towers
Average R=0.70
Median R=0.71
STD R=0.08
Skill of 3TIER Data
y = 0,9692x + 2,6531R² = 0,8772
0
20
40
60
80
100
120
140
160
180
200
0 20 40 60 80 100 120 140 160 180 200
3Tie
r 20m
ElZayt NW 24,5m
Wind energy index comaprison
y = 0,5507x + 44,931R² = 0,6706
0
20
40
60
80
100
120
140
160
180
200
0 20 40 60 80 100 120 140 160 180 200
NC
AR
ElZayt NW 24,5m
Wind energy index comaprison
"Our preliminary findings show that 3TIER wind data can
significantly reduce long-term correction error compared to
using NCAR/NCEP data, which is often the only option due to a
lack of reliable long-term ground measurements.
Per Nielsen - EMD Manager
Skill of 3TIER Data - Independent Validation
Incorporating On-site Observational Data
with
Numerical Weather Prediction Models
Model Output Statistics
(MOS)
Incorporating Observational Data
At any particular location the best way to
determine the wind resource is through direct
measurement.
3TIER incorporates observational data into
wind assessments whenever suitable on-site
data are available for
• Validation
• Statistical correction
• MOS (Model Output Statistics) is a statistical technique to
remove bias & adjust the variance of NWP model data to
better match the on-site observed data
• NWP models simulate the full structure and time evolution of
the atmosphere. MOS relates the observed wind speed to
the leading NWP predictors to improve the quality of the
long-term estimate of the wind resource.
• The output of the MOS algorithm is a multi-linear equation
that is applied to all times of the analysis on an hourly basis
(windspeed_97m * 1.25) + (windspeed_200m * 0.51) + (u_200m * 0.07) +
(temperature_0m * -0.06) + 18.93
Incorporating Observational Data - MOS
MOS-Corrected Output – Monthly-mean Variability
Validation of MOS-Corrected Time Series
Influence of observational record length
Skill at Monthly-mean Timescale
Raw Model Data MOS-Corrected Model Data
Analysis performed with Horizon Wind Energy utilizing 299 tall towers
MOS-corrected standard deviation of error for an individual month = 7.8%
Skill at Annual-mean Timescale
MOS-Corrected Model Data Raw Model Data
Analysis performed with Horizon Wind Energy utilizing 299 tall towers
MOS-corrected standard deviation of error for an individual year = 3.4%
MOS skill utilizing short observational records
A single month of observational data helps to remove bias
MOS-corrected errors decrease throughout first year of observed record
MOS skill utilizing short observational records
MOS-corrected errors decrease throughout first year of observed record
Comparing Skill of
3TIER MOS & MCP
Results based on 23 met
towers each with 5 years
of obs data
Obs data and MCP
analysis provided by
Horizon Wind Energy
3TIER MOS
MCP
Wake Modeling
• 3TIER’s super computing
capabilities allow unique
ability to model wakes in
time series across all
climatic conditions.
• Classical engineering
solutions require climatic
conditions to be condensed
into distributions, disguising
important features like
performance in atmospheric
stable conditions
Other losses
» Turbulence
» Shear
» Inflow angle
» Electrical system
» Availability
» Turbine performance
» Environmental
» Blade degradation
» Icing
» Wind sector management
» High speed start/stop hysteresis
Comprehensive Assessment
• 3TIER’s most complete solution, provides finance quality
energy assessment
• Project-wide, net energy assessment based on the last 40+
years of MOS-corrected NWP model data
• Adds a site-visit, quality control of obs data, full uncertainty
analysis, and gross-to-net analysis to a FullView Project
Resource Assessment
• Uses 3TIER’s proprietary time-varying wake modeling
analysis to understand diurnal and seasonal variability of
wakes, wind speed deficits, and turbulence intensity
Comprehensive Assessment
Full, time series simulation at every turbine across historic record
Comprehensive Assessment
Multi-staged observation QC process
Comprehensive Assessment
Comprehensive Assessment
Comprehensive uncertainty analysis highlights risk associated
with measurements, shear, spatial modeling, temporal
modeling, generation, wake modeling, etc…
Other Services
• Power Performance Testing – per IEC 61400-
12-1 standards
• Operational reforecast services – reassess the
long term production of a plant after operational
data is available
• Operational forensic services – root cause
analysis to “deep dive” into SCADA data and
attempt to explain variations on production
against expectations.
• Etc… 3TIER’s Advanced Applications group
positioned to tackle any challenges in need of
scientific solution.