Skidmore College's Innovative District Geothermal System

Submitted on July 6, 2012 - 5:22pm

Institution(s)

Skidmore College

Author(s)

Riley Neugebauer, Sustainability Coordinator, Sustainable Skidmore, Skidmore College

Paul Lundberg, Capital Projects Supervisor, Facilities Services, Skidmore College

Michael Hall, Director, Financial Planning & Budgeting, Skidmore College

Daniel Rodecker, Director, Facilities Services, Skidmore College, drodecke@skidmore.edu

Project Overview

Skidmore College has utilized geothermal heating and cooling, a renewable energy, for several years now, beginning with the installations in our Northwoods Village residential apartments, then the Murray-Aikins Dining Hall, followed by the Zankel Music Building. Now, the college has undertaken a district geothermal system for its Arts Quad, which is comprised of 4 buildings, including Zankel. This system is unique in its application and load sharing and shedding between buildings, which allows for more efficiency in the system. Planned geothermal projects at Skidmore will comprise over 600,000 square feet of building space, and 35% of campus.

Background

Following the successful geothermal application for the 10 Northwoods Village apartment buildings which house approximately 400 students, geothermal was also included in the design and construction of the Murray Aikins Dining Hall facility in 2007 and the Zankel Music Building in 2009. These buildings comprise 17% of our total square footage on campus (271,000 square feet). After the success of these projects, Skidmore made plans to add geothermal to the entire Arts Quad, which includes 3 buildings in addition to the Zankel Music Building. The Filene Building has been online since Spring 2012, and the Bernhard Theater and Saisselin Art Building will come online during the 2012-2013 academic year. The College is also working on replacement of the Dance Center heating system, as well as the heating system for the replacement buildings for the Scribner Village Apartment Complex with geothermal technology. This new apartment complex will house 466 students, and there is consideration of an additional district system there. Once all of these projects are completed within the next few years, the campus will have over 618,000 square feet of space that is heated and cooled with geothermal, or 35% of campus. Additional tentative projects may allow Skidmore to reach a goal of 50% geothermal by 2020.

Project Goals

• To provide geothermal heating and cooling to three additional buildings on campus, utilizing available land for the geothermal wells
• Improve on the efficiency of an already efficient technology (geothermal) through the use of a district geothermal system, which is an approach based on tested district systems already in use in Europe and other parts of the world where different buildings share and shed heating and cooling loads via the district system
• To utilize technology that would lessen environmental impact by utilizing a renewable energy source and reducing greenhouse gas emissions
• Reduce deferred maintenance and ongoing energy costs by replacing conventional heating, cooling, and ventilation equipment in these buildings with the geothermal system

Project Implementation

Geothermal wells are drilled down to a depth of 400-500 feet, in order to take advantage of the constant temperatures found in the earth, and many of the initial geothermal wells on campus were designed and dedicated to one building. With the recent Arts Quad geothermal design, however, Skidmore chose to add a district system instead, which was designed by Earth Sensitive Solutions and sized for 3,330 kBtu/hr heating load, and 213 ton cooling load capacity, according to Jared Fortna, Senior Engineer for the company. Having a district system means that the larger geothermal well field will contribute to heating and cooling several buildings through one controlled system. This allows the differences in the heating and cooling loads for each individual building to be accounted for, and means that each building can share or shed its heating and cooling load with the buildings next door based on what is needed in each building at any given time. It worked well on Skidmore’s campus because there is one large cooling-dominated building that was able to be combined with three heating-dominated buildings for a balanced heating and cooling load. This ultimately allows for higher efficiencies in the overall system. Paul Lundberg, Capital Projects Supervisor at Skidmore College stated that “Skidmore College would have required 125-130 geothermal wells if we had chosen to pursue one system per building instead of a district system, but because the College chose to invest in the district system, the number of wells went down to 84.” In addition, compared to conventional pumping solutions, this project is expected to save 60-80% in pump energy. John Manning, the President of Earth Sensitive Solutions, who designed the system, feels that his company is doing “cutting edge work at Skidmore College and that while this type of system is not new to the geothermal sector, there has been nothing of this magnitude or uniqueness in the Northeast”.

Timeline

• Zankel Music Building designed in 2001
• Zankel Music Building project on hold until 2007
• Zankel Music Building project construction began in 2007, and was completed in 2009 – including a geothermal well field and system dedicated to the building
• Design begins in January 2010 with Earth Sensitive Solutions, additional mechanical engineers, and Skidmore College Facilities, Project, and Finance staff, and continues for 6 months for the district geothermal system for the remaining arts quad buildings (Saisselin, Filene, & Bernhard Theater), and includes planning for the addition of Zankel to the system later.
• During the second half of 2010, design for the well field was completed so that it would fit the district system for the arts quad buildings. This included picking the well locations and mapping out where the pipes would go from the buildings to the “energy node” (central location where piping supply and return from the well field and all of the arts quad buildings will connect, as well the location where the pumps and controls will exist).
• The geothermal well (bore) field was installed in 2011. This involved bringing in drilling contractors, excavators, and a pipe fusing company to drill the 84 wells. Then, the wells were tied together in a series of parallel laterals. In total, 12 pipes enter the energy node, which is located in the back of the Bernhard Theater Building, and then go back out to the well field, so each of those pipes is connected to 7 of the wells. There are also 8 supply and return pipes, 2 per building, coming into the energy node from the buildings. Zankel’s system will be connected into the system in 2012-2013. The well field was built so that it could be expanded by leaving enough space for additional bores and including header pipes that could be connected to additional laterals in the future.
• The renovation of the Filene building began in 2010, which included the HVAC system, and the building and the geothermal connections are completely connected to the energy node and operating as of Spring 2012, a project which took thirteen months to complete.
• The renovation of the Saisselin Art building began in 2010, which included the HVAC system, and continues to be converted to geothermal, with the anticipated completion of the project by Spring 2013.
• The Bernhard Theater building project began during the 2012-2013 academic year, and is expected to be completed in 2013. This project was mainly focused on HVAC related renovations.
• The Saisselin and Bernhard Theater renovations are being done while the buildings are completely operational, necessitating phased projects that have a longer timeframe for completion.

Financing

The cost to install the geothermal district system to date, which includes the cost of engineering and design, equipment, building, drilling the bores in the well field, digging and backfilling the wells and pipes is $1.4 million. The additional anticipated cost to complete the project and tie in the remaining buildings that are not already online is $500,000. That brings to total to just under $2 million.

Skidmore received an $800,000 grant from the New York State HECAP, Higher Education Capital Matching Grant Program provided by the Dormitory Authority, which was a 3 to 1 matching grant. Skidmore provided the match for the HECAP grant. This funding comes from the college’s normal capital budget process. Additional capital budget dollars were spent for renovation and an increased scope of work throughout the project.

NYSERDA and National Grid are also committed to providing incentive funding for these projects, at an amount that is yet to be determined.

Project Results

The Filene building on campus is completely heated and cooled with geothermal at this time, as a part of the district geothermal system. Zankel music building’s geothermal system is currently operating as a standalone system now, with plans to add it to the district system in the next year or two. Renovation to the Saisselin Art building and Bernhard Theater is underway, which includes the connection of those buildings to the district geothermal system.

In Filene, the college is saving money as related to energy costs, and reducing greenhouse gas emissions from that building. Occupants are very happy with the geothermal buildings and with the energy efficiency measures included in the renovations, which allow for additional comfort levels. There are occupancy sensors that tell the lights to come on in different areas of the building, as well as tell the HVAC systems to come on above a setback level. The geothermal buildings and their new, efficient systems have led to a reduction in deferred maintenance at Skidmore, resulting in cost savings for Facilities Services.

Our current estimate is that these buildings cost approximately $110,000 per year to heat with natural gas. Therefore, the college will save that amount each year once they are all online and utilizing the geothermal system. It is also estimated that there will be 18-20% savings in comparison to the conventional chiller cooling system that was utilized by the Saisselin Art building and Bernhard Theater building, once the geothermal systems are in place in those buildings.

Lessons Learned

A campus which is looking to do geothermal for one building, or a district geothermal system, should be very involved in the process from the beginning. Do not buy a turnkey system, customize the design based on your needs and your buildings. By ensuring that you have a design firm that you feel very comfortable partnering with, you can ensure a smooth process from the start, and be clear about the levels of communication needed and integration in the design process from the various entities who are involved. Rather than have a general contractor with sub-contractors for the various pieces, try to have all the parties at the table together from the beginning.

We recommend partnering with a control firm that you trust and are happy to work with given that these systems will be in place in these buildings for a long time. Be sure to commission the buildings and the systems. Bringing in your maintenance people at the beginning so they understand the systems and how to operate them is also very important.

From an academic or communication standpoint, think at the beginning about how you want to make this educational for those who are using these buildings every day, and those who might only be passing through. How can you make something as invisible as geothermal more visible with signage or other creative options for displays?

Supplemental Materials

Keyword(s): Buildings, Energy, Financing

Admin Dept(s): Business and Financial Management, Facilities Management, Planning/Architect/Capital Projects

Discipline(s): Business, Management, and Finance, Economics, Engineering, Environmental Studies and Sciences, Geology and Earth Sciences, Sustainability Studies and Science

For more information on this project, click here.