Museum of Science
Wind Turbine Lab
Project History and
Three-Year Performance Report
Boston, MA
Why are Wind Turbines
on the Museum of Science Roof?
• Wind energy was one option explored as part of our Green Initiative,
which includes conservation, recycling, and other renewable energy
sources.
• Site, wind and structural assessment showed it was impractical to
scale wind turbines for Museum’s electrical load (9GWh/year)
– No land to install turbines, big or small. Roof is only option here.
• Little data on small-scale wind turbines are available from the built
environment
– “Built environment” includes turbines within influence of human
construction, not just on rooftops or building-integrated
Goals of the MOS Wind Turbine Lab
• Testing a variety of commercially available small-scale wind turbines
roof-mounted in our urban environment
• Serving as a community resource for both professionals and the
general public
– A lesson in critical thinking about energy technology
– A practical demonstration and laboratory; experience; data
• An experiential part of a new Museum exhibit
• A landmark for Boston, Cambridge, New England
• A statement about the importance of renewable energy
And it also generates clean energy…
Three-Year Summary
2010 through 2012
• The wind turbines average 4,229 kWh
clean electricity per year.
–
–
–
–
–
15.6 kW installed, grid-tied
55% of average MA home annual electricity
Museum requires > 1,000 times MA house
12.70 MWhr total
Avoid over 5,100 pounds of carbon dioxide each year
• No issues with noise, vibration, ice throw, flicker, bats, other
environment problems; just two bird strikes in 5-year lab history. Our
neighbors like them, too.
• Not cost effective at this site
– Roof installation costs were high; Complex project
– The Museum does not have a good wind regime
•
Average Wind Speeds ~ 3 m/s; Recommended average 5 m/s
• Project Planning
• Data Analysis
• Turbine Performance
• Lessons Learned
Complex Site
PUBLIC
SAFETY
STRUCTURE
But wait, there’s more!
Neighbors
FAA / hospital / military flyway
Historic District
(MA, Boston & Cambridge)
Wetland
DCR Land
Birds? Bats?
Endangered species?
Museum Wind Study
• Multiple locations for measurement
– Parapets
– Tower
• 3-month study correlated local data to Logan to estimate local
annual pattern
• Winds recorded for another 9 months
• Moved anemometer 1 to future Proven location
• Full report available at mos.org/WindTurbineLab
Turbine Criteria
• Commercially available, residential-scale
• Size & weight appropriate for roof installation
• Responsive in our wind regime
• Within budget
• Variety of designs
– Downwind, upwind, architectural, vertical
• Manufacturer willing to accept the challenge
The Turbines
Windspire Energy
Windspire
1.2kW @11m/s 10 m tall
Proven Energy
Southwest Windpower
Skystream 3.7
Proven 6
6kW @12m/s 5.5 m diameter
2.4kW @13m/s 3.7 m diameter
Cascade Engineering
Swift
AeroVironment
1kW @11m/s 2.1 m diameter
AVX1000
5 x 1kW @13m/s 1.8 m diameter
The Exhibit: Catching the Wind
• Project Planning
• Data Analysis
• Turbine Performance
• Lessons Learned
Data Collection - Power
Data Collection - Wind
MOS Wind Turbine Lab
Data Analysis
• Scatter-plot power vs. wind data compared to
published power curves
• Energy and wind distribution charts
• Comparison metric is Energy / Swept Area
• Ad-hoc analyses
Understanding Power Curves MOS Data
• The Museum samples data every 2-3
seconds, after inverters, transformer.
– Wind Direction
– Power & Energy for each turbine
– Wind Speed for each turbine’s
anemometer
• Data aggregated into 10-minute intervals, includes wind speed and power
averages, min, max, std dev.
• We create scatter plots of 10-minute average power vs. 10-minute average
wind speed; compare to manufacturer’s graphs.
Understanding Power Curves Rated Power, Rated Speed
•
Power Curves are graphs that plot the power a turbine generates at different
wind speeds. Defines expected performance, but not energy in local wind
regime.
•
Wind Speed for “Rated Power” is not yet standardized across market,
complicating comparisons.
Vertical axis is kW
•
Example: Note difference below
between power at 12 m/s and 11 m/s.
Power
Wind Speed
AVX1000
1 kW
@ 13m/s
Proven 6
6 kW
@ 12m/s
Skystream 3.7
2.4 kW @ 13m/s
Swift
1kW
@ 11m/s
Windspire Standard
1.2 kW @ 11m/s
Windspire Extreme Wind
1.2 kW @ 13m/s
Understanding Energy
•
Power is proportional to wind speed cubed and swept area: ½ρAV3
–
•
“Rated Power” tells you about size of generator and rotor, not how much energy you can expect.
Energy = Power * Time
–
–
•
Energy depends most strongly on wind speed and duration
• How fast, how long, how often
Energy is what the end user cares about
Wind at MOS rarely reaches the speeds at which our turbines are rated (11-13m/s)
–
–
•
Beaufort Wind Scale Number 6: “Strong Breeze”
• 25 – 31 mph (11–14 m/s)
• Large branches move; river is choppy; umbrella use is difficult
Less than 1% of wind here over 20 mph, likely typical of populated areas
MOS turbines do produce over 4.2MWh per year
–
–
MOS WTL mean wind speeds: 6.2 – 8.3 mph (2.8 – 3.7 m/s)
Recommended average wind speed 11 mph (5 m/s)
“High wind” distribution
(dark blue, right)
better correlates with
energy generation
(above)
than using average
wind speeds (below).
Wind Direction
• Project Planning
• Data Analysis
• Turbine Performance
• Lessons Learned
Skystream 3.7
Horizontal axis, Downwind ; Passive yaw
3.7-meter rotor; 10-meter tower
Closest to “plug and play” for 3.5 years.
Out of service Oct 2012 thru Dec 2012.
16.5% of average MA home’s electricity.
Run plasma TV 10 hours a day.
10
hours
Proven 6
Horizontal axis; Downwind; 5.5-meter rotor; 9-meter tower
Largest generator and rotor of the Museum turbines.
Produces the most energy but underperforms at higher winds. speeds.
Wiring adjustment August 2012
28.7% of average MA home’s electricity.
Run plasma TV 18 hours a day.
18
hours
Proven Power Curves
AVX1000 (5 Units)
Horizontal axis; Upwind; 1.8-meter rotor.
These turbines act independently,
but we add their power together.
Hardware and inverter problems repaired;
Improved, still underperforming.
6.8% average MA home’s electricity.
Run plasma TV 4 hours a day.
4
hours
Swift
Horizontal axis; Upwind; 2-meter rotor
The computer model picture below shows
how wind from the river slows down when
it gets to the Swift (at the small blue swirl
on the roof).
1.2% average MA home’s electricity.
Run plasma TV less than an hour a day.
TRC/Ansys Computational Flow Model
<1
hour
Swift: Investigating Power Curve’s Lower Limb
Why do some high-wind records yield very low power?
- CFD model and observation indicates in SW wind Swift often
yaws without spinning.
- Can anemometer (2 inch diameter) measure high winds in
eddy that Swift (2 meter diameter) cannot utilize?
- Are effects seasonal? Directional? Vary by wind bin?
• At wind speeds over 6 m/s, 82% of the data records follow
the power curve.
• Roof drag and structural obstacles may impede Swift’s
operation, but most of the data does follow the power curve,
performing to spec.
N
NNW
NNE
NW
NE
WNW
ENE
W
E
WSW
ESE
SW
SE
SSW
SSE
S
Windspire Standard Model
1Jan2010 – 30Jun2011
Vertical-axis; 6-meter tall rotor
Cut-out logic reduced access
to high energy wind, but
standard model tracks power
curve well to 8 m/s.
Due to inverter issues,
Windspire shut down Jan, Feb,
most of Aug, half of Sep, end
of Dec.
Nearby chiller fan may affect
turbine or anemometer during
summer months.
Windspire Extreme Wind Model
Vertical-axis; 4-meter tall rotor.
1.6% average MA home’s electricity.
Run plasma TV one hour a day.
1
hour
Windspire Extreme Wind
model replaced Standard
model July 11, 2011
-
Designed to cut-out at higher
wind speed (40mph) and
recover much faster.
- Reduction in swept area shifts
power curve to the right.
- Tracks power curve well,
except:
Depressed power curve reliably
occurs during hot weather months.
Specific causes unclear.
Windspire Power Curve Comparison
Standard and Extreme Wind Models
How to Compare?
Energy / Swept Area
Swift
Windspire
Skystream 3.7
SWEPT
AREA
Proven 6
AVX1000
Comparing Different Wind Turbines
(2010 – 2012 data, except where noted)
Annual
Energy/
Swept
Area
(kWh/m2)
Avg
Wind
Speed
(m/s)
Rated
Power
(kW)
Energy/Year
(kWh)
(EIA avg 2010,2011)
Skystream
118
2.9
2.4
1278
16.5%
Performing as expected here.
Out of service Oct2012 thru
Dec2012.
Proven
93
2.8
6.0
2218
28.7%
Generally performs well; Power
plateaus early.
Improved after rewiring
Aug2012.
AVX1000
40
3.7
5.0
525
6.8%
Highly directional. Improved
after 2010 repairs, but still
underperforming.
Swift
25
2.8
1.0
90
1.2%
Some issues with siting; data
tracks power curve most of the
time.
Extreme Wind
25
2.9
1.2
123
1.6%
Replaced Standard model
11Jul11. Performing as
expected here. Seasonal site
issues.
24
3.1
1.2
176
2.2%
Out of service 4 months of 12.
Seasonal site issues. Shut
down Dec2010.
TURBINE
MA Home
(5 units)
Windspire
(11Jul2011-31Dec2012)
Standard
Windspire
(2010 only)
Notes
Performance over Time
• Project Planning
• Data Analysis
• Turbine Performance
• Lessons Learned
MOS Lessons Learned
• Successful experiment!
– Generates 4.2 MW-hr clean electricity, avoids 5,100 lbs carbon dioxide annually
– Attractive addition to Museum; Draws interest on renewable energy
– Have provided detailed data and project information to over 1,300 people:
industry professionals, universities, government and the general public,
plus all visitors interacting with the Catching the Wind exhibit
• Be clear on project goals.
– Energy? Education? Economics?
– Seek stakeholder buy-in early and often.
• Measure wind profile as close to hub height as practical.
– Understand how much energy you can expect in your wind regime.
• Installation sites needed to be a compromise here.
– Building roof structure, permitting, and wind rarely converged
– Roof mounting some of these turbines expensive compared to ground installation.
The Team
Renewable Energy Trust / Mass CEC
Dick Tinsman, now with Criterium Engineers
rtinsman@criterium-engineers.com
Rapheal Herz, now with Johnson Controls
Raphael.Herz@jci.com
Jim Christo, now with Alteris Renewables
jchristo@alterisinc.com
Marybeth Campbell, now with the Massachusetts
Clean Energy Center
MCampbell@MassCEC.com
Christie Howe, Massachusetts Clean Energy Center
chowe@MassCEC.com
Underwriters
Museum of Science
David Rabkin, Director for Current Science and Technology
Paul Ippolito, Director, Facilities
Steve Nichols, Project Manager, IIT
Marian Tomusiak, Wind Turbine Lab Analyst
Boreal Renewable Energy Development
Bob Shatten, Principal
Tom Michelman, Principal
Alex Weck, Principal
Michael Alexis, Principal
ANSYS/TRC
Valerio Viti, Sr. Fluids Specialist
Chris DesAutels, Sr. Meteorologist
Lloyd Schulman, Sr. Meteorologist
Apterra Technologies
Ted Schwartz, Principal
Nexamp, Inc.
Will Thompson, VP, Integration
Phelan Engineering
Paul Phelan, Jr., P.E.
Richard Gross, Inc.
Richard Gross, P.E.
Rubin and Rudman, LLP
Keren Schlomy, Partner
Kresge Foundation
Cascade Energy
Museum of Science and its supporters
And the Extended Project Team
drabkin@mos.org
pippoloto@mos.org
snichols@mos.org
mtomusiak@mos.org
bshatten@boreal-renewable.com
tmichelman@boreal-renewable.com
aweck@boreal-renewable.com
malexis@boreal-renewable.com
valerio.viti@ansys.com
cdesautels@trcsolutions.com
lschulman@trcsolutions.com
ted.schwartz@apterratech.com
wthompson@nexamp.com
paulphelan@comcast.net
rgross@ieee.org
kschlomy@green-mail.org
Shaw Welding Company
Rick Shaw, President/CEO
rick@shawwelding.com
Titan Electric Corporation
John Gill, President
jgill@titan-electric.com
View from Museum of Science Garage Roof
One Science Park, Boston MA August 2011
David Rabkin
Farinon Director,
Current Science and Technology
drabkin@mos.org
mos.org/WindTurbineLab
mos.org/Energized
September 2014
Marian Tomusiak
Wind Turbine Lab Analyst
mtomusiak@mos.org