Alliant Energy Solar Demonstration Project October 4, 2017

Transcription

1 Alliant Energy Solar Demonstration Project October 4, 2017

2 Background: The Madison Solar project is a 291 kw installation Completed and put in-service February 26, ,300 modules 10 different modules types (varying orientations and technologies) Monocrystalline, polycrystalline, thin film, reflective and hybrid arrays Battery Energy Storage System (BESS) 18 Electric Vehicle charging stations EPRI Collaboration Objective: Create a Learning Lab where various solar technologies can be studied to provide operational insight. Data shared through a joint EPRI/Alliant Energy public dashboard. Learn from our first solar installation for future generation projects. Partnership: Three year EPRI study to demonstrate, research and track the performance of solar technology in the Midwest compared to similar installations in Denver Colorado and Birmingham Alabama. 2

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4 Parking Canopies Quantity: kw total capacity Another application for solar install Industry Structures Quantity: 5 2 kw each South facing 15 tilt angles Solar Café Tables Quantity: 2 Freestanding Power Outlets LED Lights 4

5 Rooftop Solar 9 different modules 8 different manufacturers 3 different technologies 95 kw total capacity EPRI Study Solar Lab Quantity: 5 3 kw each Several different tilt angles and orientations for comparison EPRI Study 5

6 Curve Structures Quantity: kw each South facing 34 tilt angle Trestle Structures Quantity: 9 4 kw each South facing 5 & 10 tilt angles Lift Structures Quantity: 4 3 kw each 35 tilt East, West & South Facing 6

7 Monocrystalline Highest efficiency rates Space efficient Longest life span Most expensive More efficient in warm weather 15-20% efficient Polycrystalline Costs less to manufacture Amount of waste silicon is less Lower space efficiency Most commonly used 13-16% efficient Three Common Module Types Thin Film Mass production is simple Can be made flexible, more applications High temperatures and shading have less impact on solar panel performance Low space efficiency to degrade faster 9-14% efficient 7

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9 Solar Project Annual Energy Enough to power approx. 45 homes 147 tons of coal avoided Equivalent to switching 9,775 incandescent light bulbs to LED Offsetting approximately 10% of building load Energy Efficiency improvements saving an additional 5% 9

10 Electric Vehicle Charging 18 Level 2 stations 2 ADA accessible Open to staff and the public Currently no cost to charge Battery Energy Storage System Quantity: 1 30 kwh capacity Investigations will include site demand reduction, solar firming & spike reduction. EPRI Study 10

11 11 Madison Solar Demonstration Project Lesson Learned QA/QC was a larger than expected task as we experienced multiple inverter communication issues, inverter failures and varmint damage. Large scale solar is not install and forget and performance needs to be monitored. Substantial IT and Generation Engineering efforts were required to get all communication interfaces talking and scaling correctly. Battery storage system proved to be too small to provide usable data for site demand reduction adding an additional 250 kwh battery. Modeled vs. Actual performance proved to be very accurate using PVWatts calculator. Cloud Enhancement - On partly-cloudy days, solar intensity (irradiance) can exceed the intensity of direct sunlight at times. Employee EV ownership increased from 2 in 2014 to 29 in Strong interest from customers and organizations to learn from Alliant s Installation. At least two years of data needs to be collected before any deliverables/trends can be developed. We need to be cautious not to share data trends and recommendations too quickly due to short time frame of our data sampling.

12 Actual vs. Expected Performance Madison Solar Demonstration Project December 2016 gave us our first look at the effects of snow! System has been exceeding model expectations (avg. about 110% of model results) In December, 3 snowfall events reduced performance to anywhere from 30% to 80% of expected 120% 100% 80% 60% 40% 20% 0% Abnormally Sunny November 3 Major Snowfall Events in December Rooftop Aggregate Architecture Aggregate Solar Lab Aggregate Carport Aggregate 12

13 "Production Factor" - % Madison Solar Demonstration Project Temperatures stayed low after the 3 major snowfall events snow melt could not relieve the loss in performance Arrays that recovered most quickly: Arrays with steeper tilt angles (snow slides off) Arrays with advanced micro inverters (better production with partial snow coverage) Madison Power Production 13 Snowfall Events with Accumulation Light Snowfall Event followed by RAIN

14 Carports V shape shows slow recovery Trestle Structures Low Tilt Angle West side of Roof Panels completely drifted over 14

15 Questions? 15