Case Study
415.402.0888 | MKThink.com
HNEI Kauai & O’ahu, HI Test Platform Performance Analysis
Aloha Energy Neutrality
Investigating data-driven solutions for commercially viable energy conservation
SIGNO uddenberg Technical Projects Lead Signo led the project requirements development and guided the project through design of experimentation, procurement and installation of equipment, performance measurement & monitoring, and analytic findings and performance interpretation. Results from the study were submitted and accepted for presentation to ACEEE, the preeminent international conference on energy-
HAWAII NATURAL ENERGY INSTITUTE Established in 1974, HNEI coordinates and undertakes the development of natural energy sources for Hawaii. The institute conducts energy research focused on technically sound, cost- effective solutions and practical strategies for commercially viable renewable energy implementable in Hawaii and the world at large.
CHALLENGE | Design a
Hypothesis | A data-driven,
research-based framework for
analytic framework that relates
cost-effective solutions that
actual performance data, predictive
minimize energy consumption in
energy models, and IEQ guidelines,
buildings while maintaining high
will inform an understanding of
standards of user comfort
the factors that affect building performance and the technology
Context | Hawai’i has a
improvements to optimize energy
dramatic combination of high
use
energy costs, vulnerable fossil fuel supply, and a state mandate
APPROACH | MKThink
to develop alternative, local
conducted a 2-year study to
energy sources. HNEI and its
compare the simultaneous
funding sources have identified
performance of 6 educational
Hawai’i as an ideal laboratory
classrooms. The classrooms
to study climate and cultural
represent 3 building typologies
factors and experiment with
common to Hawai’i’s 255 public
energy solutions that can be
schools. Studies were conducted at
applied locally and to the greater
3 sites in different microclimates on
Pacific region.
the islands of Kauai and O’ahu.
Hawai’i depends on fossil fuels
Architectural variables were
for 90% of its energy needs and
controlled for with a test set that
imports 100% of its crude oil.
included a) common building
Its electricity costs are 25 - 35
designs at different sites, b)
cents/kWh which is two times
neighboring buildings at the same
above the national average.
sites, and c) different building types
In 2015, Hawai’i set a target
in the same microclimates.
Renewable Portfolio Standard of 100% by 2045.
Each test building was equipped with 16 sensors to measure 11 KPIs correlated to 5 microclimate factors.
the IDEAS company for the built environment
415.402.0888 | MKThink.com
HNEI Kauai & O’ahu, HI Test Platform Performance Analysis
PROJECT DATA
RESEARCH Questions | MKThink focused the overarching hypothesis with three key research questions:
Type EDUCATION Government Location Kauai & O’ahu, HI Dates 2013 - Ongoing SIZE 6 buildings ranging in size from 840 sf to 1,280 sf
1.
Is performance consistent across classrooms with similar architectural and building system features?
2. Do platforms perform as predicted by models? 3. Do platforms perform within standard guidelines: ASHRAE Adaptive Comfort Model, Air Quality, LEED, CHPS, OSHA? Each question was dissected into metrics with criteria for comparative analysis. Building performance is defined by a) energy neutrality (solar PV production minus energy consumption), b) energy use (overall and by individual
SERVICES SCOPE
building system), c) indoor environmental quality (thermal
Experiment Design
comfort, air quality, lighting quality), and d) system
Test Site Selection
performance (day lighting provided).
Data Services
InSights & INTERPRETATION | Analysis of the
Test Equipment Determination, Procurement, and Deployment Analysis of Experiment Results
ANALYTIC FINDINGs •
•
•
•
•
•
HVAC energy use varied by 75% for the same building types and accounted for up to 55% of weather-related energy use. Energy use varied by 31% between the same building types in the same climate. 85% of HVAC energy use occurred under the best practice min. set point: 82°F. High performance buildings were “thermally comfortable” 21-77% of the day based on ASHRAE 55 guidelines Kawaikini FROGs: Energy consumption was 46-61% less than the predictive models anticipated (16-38% better than the optimal case) KW East: Delivered the most.
multivariable data set produced the following results: 1.
Building performance varied across all buildings regardless of architectural and environmental factors. Systems were used outside of programmed settings, indicating that user preference and behavior may play a large role in performance.
2. The high performance building designs performed better than optimal model predictions, but showed individual system usage that differed from the model. 3. High performance buildings maintained air and lighting comfort within standards more than 95% of the time but struggled to maintain proper thermal comfort thresholds. Generally they were too hot and humid, but occasionally too cool and dry, signaling a need to better understand behavior around thermal comfort
CONCLUSIONS | The data interpretation and insights informed two primary recommendations: • Implement strategies to standardize user behavior (user education and/or behavior-based building systems) to optimize the benefits of high-performance buildings • Conduct focused studies on user thermal comfort perception and behavior to determine the value of comfort and further reduce building energy use
comfort per unit of energy. Overall, the analytic framework used for the study enabled a better connection among performance and resource inputs, while controlling for confounding factors.
the IDEAS company for the built environment
415.402.0888 | MKThink.com
HNEI Kauai & O’ahu, HI Test Platform Performance Analysis Test Buildings
KW East
KW WEST
Ilima
EWA P6
EWA P1
EWA D36
Building Types
Energy Use Intensity kWh/yr/Nsf
1.1
1.7
3.8
3.8
1.1
3.0
Weighted Comfort Scores based on established Building Guidelines
62%
86%
54%
52%
43%
78%
% Comfort Delivered per Unit of energy Used
Higher Performance
57% com/EUI
50% com/EUI
47% com/EUI
14% com/EUI
11% com/EUI
26% com/EUI
the IDEAS company for the built environment
415.402.0888 | MKThink.com
HNEI Kauai & O’ahu, HI Test Platform Performance Analysis
HVAC Energy Use Correlated to outdoor air temperature HVAC energy use coefficient of determination with outdoor air temperature varied by 75% (R 2 = 0.25 to 0.55) for the same building types and accounted for up to 55% of weather -related energy use .
2200 kWh
2000 kWh
KW East KW West Ilima P6 P1 D36
1-Year Study Period: 7/1/14 - 6/30/15 All Hours
1800 kWh
1600 kWh
1400 kWh
1200 kWh
1000 kWh
800 kWh
600 kWh
400 kWh
200 kWh
MONTHLY ENERGY TOTALS Energy consumption across buildings has seasonal variation. Factors likely affecting monthly patterns include weather, school programming, and occupant preferences.
the IDEAS company for the built environment
20 15 /1
2 20 14 /1
1 20 14 /1
0 20 14 /1
20 14 /9
20 14 /8
20 14 /7
0 kWh