Sustainability Annual Performance

In Fiscal Year 2023, NREL demonstrated its commitment to addressing the pace of climate change, energy and water efficiency, and building community partnerships to reach net-zero emissions goals.


NREL's energy and resilience programs support sustainability efforts through a focus on energy efficiency, sustainable buildings, and ongoing commissioning and innovation.

Energy Mix

Three major factors contributed to a 21% increase in calculated energy use intensity on NREL's South Table Mountain campus in Golden, Colorado (this excludes the lab's high-performance computer):

  1. An increase in research plug load and laboratory needs
  2. Significant leaks in the hot water system, planned for repair in Fiscal Year 2024
  3. The addition of one new facility.

One hundred percent of the total grid electricity that NREL purchased for its Flatirons Campus in Arvada, Colorado, was clean energy through Xcel Energy's Renewable Connect Flex green tariff program.

South Table Mountain Campus
Fiscal Year 2023 Energy Use


KBtu – thousand British thermal units

Flatirons Campus Fiscal Year
2023 Energy Use


MBtu – million British thermal units
*Flatirons Campus exported 11,599 MBTU

Data Center Energy Use

Power usage effectiveness (PUE) is the standard ratio used to calculate how efficiently data centers use energy. In Fiscal Year 2023, NREL had PUE scores near the ideal 1.0, with its High-Performance Computing Data Center scoring 1.04 and its 13-year-old Research Support Facility Data Center achieving an average monthly PUE of 1.32.

See Sustainable and Net-Zero Buildings on NREL Campuses for more details about how our buildings achieve high levels of energy and water efficiency.

Greenhouse Gas Emissions Performance

NREL increased greenhouse gas emissions from energy (including natural gas and grid electricity) by 19%. This takes into account NREL's green tariff electricity purchase.


T&D losses – transmission and distribution losses


MTC02e – metric tons of carbon dioxide equivalent

NREL decarbonization efforts in Fiscal Year 2023 included:

  • Completing an investment-grade audit
  • Awarding its first task order for a new energy savings performance contract, which includes upgrading the last four facilities on its Flatirons Campus from natural gas to electric heating.
  • Signing a memorandum of understanding with Xcel Energy to develop a carbon pollution-free electricity tariff with 24/7 matching for at least 50% of participating federal load.

Digital Campus Replicas as Planning Tools

NREL is developing digital twins of its Colorado campuses to conduct campus planning and communicate complex tactical planning through custom dashboards. The platform maps the physical world of its Colorado campuses to a virtual environment to inform strategic decisions. These considerations de-risk and optimize current energy systems and provide insight into how future energy systems can operate and perform.



NREL's waste reduction and pollution prevention programs support sustainability efforts through a reduce/reuse/recycle/re-buy philosophy, composting, the chemical management system and excess chemical inventory, and pollution prevention initiatives.

Municipal Waste Diversion

In Fiscal Year 2023 NREL's waste management performance resulted in an overall diversion rate of 47% from landfills. Recycled materials included batteries, computer monitors, electronic waste, lightbulbs, paper, and Styrofoam.


C&D – construction and demolition.

Construction and Demolition

During construction of NREL's Research and Innovation Laboratory, NREL increased its wood recycling and reduced the amount of construction and demolition materials and debris sent to treatment and disposal facilities.

Sustainable Procurement

NREL made strides in sustainable purchasing in Fiscal Year 2023 by:

  • Receiving the 2023 five-category EPEAT (Electronic Product Environmental Assessment Tool) Purchaser Award for its exceptional commitment to sustainable procurement
  • Improving the lab's internal purchasing catalogs across groups of items such as IT hardware, laboratory supplies, and tools and hardware to improve operational efficiency and reporting and streamline compliance
  • Moving from a traditional gasoline-powered equipment provider to 100% electric-only equipment under a new subcontractor
  • Improving resilience by reducing the risk of fires on-site through the removal of combustible fuels.


Zero-Emissions Fleet

NREL analysis shows all the lab's fleet vehicles could be converted to battery electric vehicles, once commercially available, and that most vehicles would only require overnight charging. NREL has 12 zero-emission vehicles (ZEVs) in its fleet and two more ZEVs on order.

In Fiscal Year 2023, NREL received and deployed the BEAM EV ARC 2020 charging station at its Golden, Colorado, campus. The system has two Level 2 chargers, four Level 1 chargers, and a 20-kilowatt-hour battery that can charge fleet vehicles. The system is powered by solar photovoltaic and mobile, which allows relocation as required.


NREL's continued water-efficiency efforts include monitoring and optimizing campus water use.

Water Mix

NREL's water use increased 2% in Fiscal Year 2023, largely due to the expansion of the High-Performance Computing Data Center and a leak in the South Table Mountain campus' hot water system. These increases were mitigated by a reduction in irrigation and repairs to additionally identified leaks.

The lab continues to use water primarily for cooling towers, steam boilers, clean rooms, and the High-Performance Computing Data Center. Sources of unattributed water use include unmetered water use within a clean room in the Science and Technology Facility on the South Table Mountain campus and a fire water system leak on the Flatirons Campus that was repaired at the end of Fiscal Year 2023.

Water Savings

The first task order for the NREL energy savings performance contract includes a water efficiency measure to retrofit water fixtures across the South Table Mountain and Flatirons campuses. The measure will save a significant amount of water and address deferred maintenance across both campuses.