case study, news
Energy Conservation: Waters Laboratory
Project Summary
The Waters lab energy conservation project resulted in savings of over $300k a year, a 1.6 year project payback with $728k utility incentive. The client's annual emissions were reduced by over 1,300 metric tons of CO2.
Problem
Waters, a laboratory instrument and software company, was renovating their 100,000 sq. ft. building and tasked SDG with performing an energy study for potential building upgrades. The company was redesigning spaces for lab and office use and wanted to uncover potential building efficiency gains. SDG’s study was split into two phases due to upcoming structural changes of the building which necessitated an expedited timeline for any equipment impacted by the structural changes.
Phase I
The first phase, which necessitated expediency so that the steel work could be completed before the arrival of winter, focused on improving the building chilled water systems. SDG performed measurement and analysis under National Grid’s Comprehensive Chiller Analysis (CCA) and Design 2000 Plus (D2+) program.
The base case consisted of installing three 174 ton rooftop air-cooled chillers. The proposed system featured two 250 ton higher efficiency water-cooled chillers with a significantly lower connected/operating power.
Phase II
In phase II, SDG looked at the energy conservation measures outlined below as part of the D2+ program.
- Lighting: higher efficiency lighting design with lower wattage technology and control strategies such as occupancy and daylighting control.
- Roof Insulation: increased roof insulation resulting in reduced roof energy losses.
- Low flow laboratory hoods: hoods operating at reduced face velocities thus reducing total air change rates (compared to standard laboratory hoods with face velocities of 100 feet per minute). The measure also considered a demand ventilation control system for the laboratory hoods which modulated supply/exhaust to each hood. Flow modulation was based on sash position and room occupancy.
- CHW Variable Flow Pump System: higher efficiency chilled water pumping system with VFDs to reduce pump power consumption when cooling loads are reduced.
Challenges
The project timeline had to be accelerated because of the structural work being done in the building. This meant expedient coordination between the owner, the designers, the contractor, the utility, and SDG to design the system and select the equipment, gather all the information for the analysis, and complete all the paperwork.
Our Approach
For this project an integrated approach was necessary, where the client and contractors assisted in preliminary design to determine design and load requirements. Engaging National Grid at the outset also facilitated the selection of higher efficiency equipment because the calculated incentives helped to offset the incremental cost. We analyzed each of the energy conservation measures using custom software to determine the energy and monetary savings. Our deliverables included a report of the analysis assumptions and results, printout(s) and electronic version of savings calculations, and information for incentive applications.
Results
At the time, the project was awarded the largest incentive the utility had ever given. The project yielded many positive benefits for the customer.
- Annual emissions reduced by over 1,300 metric tons of CO2
- $305,700 in electric and natural gas savings per year
- Over $728,000 incentive from the utility
- Less than 2 year pay back after the utility incentive
- Savings of 1,108,000 kWh of electricity annually with 550 kW peak power reduction
- Savings of over 99,000 therms of natural gas annually