Reference Plant: Solar-Log® Partner Trane Helps Schools Reduce Electricity Costs with Solar


Installer: Trane,

Location: Dighton, MA

Nominal Power: DES 117 KW , DMS 198 KW, PRES 171 KW, BMS 229.5 KW, DRRHS 639 KW

Expected Annual Output: DES 134,066 KWh, DMS 260255 KWh, PRES 221747 KWh, BMS 280442 KWH, DRRHS 797494 KWH

Inverter Type: SMA 24000 TL

Mounting system: Carport Canopy

Monitoring: Solar-Log 2000/ Solar-Log 2050 Revenue Grade Meter, Solar-Log Web Enerest™ XL

While best recognized as a global leading manufacturer of HVAC equipment and Building Automation Systems, Trane also offers comprehensive energy services providing self-funding energy and cost saving projects to building owners globally. Trane not only provides HVAC equipment, building automation systems, facility improvement measure and renewable energy efficiency solutions, but also offers ongoing services and support to sustain optimal facilities operation, and energy efficient operation for the long term.

“Local officials and K-12 administrators appreciate our ability to combine energy conservation measures in their facilities, with a customized scope of renewable energy systems all through one cohesive agreement” said Leo F. McNeil, Regional Director of Comprehensive Solutions at Trane, when discussing the addition of solar PV into their portfolio. “It makes sense to begin by reducing the amount of energy consumed in facilities, and then determine the appropriate amount of power to be generated on-site through renewables. In this way, we can maximize operational and economic benefits for our clients.”

Trane recently developed and installed a 1.2 MW solar PV portfolio for the Dighton Rehoboth Regional District (DRRSD), in Massachusetts. The district’s challenges were outdated HVAC and control systems in all five schools, resulting in excessive utility consumption and related utility costs. Through a performance contract, Trane updated all of the schools to improve the quality of the learning environment in classrooms throughout the district, while substantially reducing energy consumption. Then, solar PV systems were designed and installed - all funded with a lease with no additional expense to taxpayers. The lease is paid for over time using resulting energy savings and renewable incentives from the Commonwealth of Massachusetts. The solar PV portfolio consists of 5 carport-canopies ranging in size from 117kW to 639kW.  (There are 12 distinct carport structures at 5 locations throughout the district. The Solar-Log® system contains 5 sites:

Beckwith Middle School        3 carports
Dighton Elementary School    1 carport
Dighton Middle School        1 carport
Palmer River Elementary    2 carports
DR High School            5 carports    
See sites here:

DRRSD has chosen to own the solar systems instead of executing a Power Purchase Agreement where a separate entity would own them, and provide a discount on a portion of electricity purchased by the district. Accordingly, through this direct ownership option, the district retains 100% of savings realized by generating ~75% of their electricity on-site, as well as all of the available incentives from the Commonwealth of Massachusetts.  

Trane selected Solar-Log® based on its ability to report solar power production annually to the Commonwealth of Massachusetts SREC Solar Renewable Energy Credits system. This ensures ongoing revenues to DRRSD in compliance with the system. In addition, the Solar-Log® system has an internet accessible feature to observe real-time production on any given day, plus cumulative power consumption data over time.

“We found the Solar-Log® system to be an ideal fit based on their production reporting capability,” said McNeil, “In addition, the internet accessible real-time energy production Dashboard is a great tool which the district can also use to educate the students.”

Trane installed Solar-Log 2050 revenue grade meters along with Solar-Log® data loggers. The Solar-Log® solutions provide accurate production values, error alerts, and a comprehensive software portal including the Solar-Log® end-user Dashboard.

In addition to providing the performance data needed to ensure that their solar PV plant is running free of errors, Solar-Log® monitoring can also be used to help teach students the importance of energy conservation and renewable energy. Each of the five schools has the ability to display the Solar-Log Dashboards on large flat screen monitors located where it is easily visible to students, faculty, parents, and visitors.

The Dighton Rehoboth schools now make approximately 75% of the energy used by the district on an annual basis. Overall, there is a 62% reduction in their total energy spend.