Reaching the 500-building milestone, our team of operational advisors paused this week to look back at the opportunities we identified over our careers, trends, and where our clients found the greatest returns. While equipment upgrades made the list, the most compelling business case lies with operational improvements and wringing out the savings from existing equipment. Here is our top 10:

1. Align equipment operations with occupancy schedules. Simply put, if it does not need to be on, turn it off. Look for overridden or failed HVAC and lighting controls, and align equipment operations with occupancy schedules. This very basic concept can yield immediate savings.
(Typical payback period: Immediate; Application: All building types)

2. Take advantage of free cooling. Most commercial buildings require cooling year-round regardless of their geographic location. When outside air temperatures fall below indoor temperatures and humidity levels are low, a building’s cooling load can be offset using air- and water-side economizers. Energy is saved by turning off the mechanical cooling.
(Typical payback period: Immediate if infrastructure is in place; Application: Buildings with air- or water-side economizers)

3. Program enhanced BAS control sequences. Do you own a million-dollar time clock? Building automation systems (BAS) are powerful tools with great capabilities. By programming enhanced control sequences that dial-in equipment operations, significant value can likely be harvested from your existing BAS.
(Typical payback period: 1-4 months; Application: Buildings with BAS controls)

4. Proactive HVAC Preventative Maintenance. Punching chiller tubes, thoroughly cleaning HVAC coils, changing filters, fan belts, etc. are low-cost activities included in most preventative maintenance (PM) programs. However, PM schedules are not always appropriately developed and implemented. Proactively addressing PM, rather than reacting to equipment failures, can have a significant impact on utility costs and future capital costs through improved equipment reliability and longevity.
(Typical payback period: 1-4 months; Application: All building types)

5. Control air leakage into the building. When outside air leaks into a building, an equal volume of indoor conditioned air escapes from the building, along with the energy used to heat or cool the air. Sealing openings in the building envelope will reduce energy costs and improve occupant comfort.
(Typical payback period: 1-6 months; Application: All building types)

6. Strategic air and water flow. Buildings are designed for air and water to flow through mechanical equipment at specific rates to maximize efficiency. As setpoints and flow rates drift over time, comfort and efficiency suffer. Commissioning a building helps maximize equipment efficiency and comfort and is a cost-effective strategy to reduce energy waste.
(Typical payback period: 1-6 months; Application: All building types)

7. High efficiency plumbing fixtures. Since 2010, the cost of water has increased by an average of 41% across 30 major US cities ( Retrofitting plumbing fixtures to improve efficiency is one of the most cost-effective ways to manage this risk. Before proceeding, be sure to test the aerators, flush valves, and showerheads to ensure compatibility, performance, and occupant comfort.
(Typical payback period: 3-6 months; Application: All building types)

8. Smart irrigation controls. How many times have you seen irrigation sprinklers operating when it is raining? For many years, rain sensors and adjusting time clocks was the best strategy. However, new smart controls schedule irrigation times per local weather patterns, rainfall, soil moisture content, water percolation rates, . . .  Supported by a strong business case, smart irrigation controls are becoming more prevalent amid mounting water regulations and severe droughts in many areas of the country.
(Typical payback period: 3-6 months; Application: All building types)

9. LED lighting and controls. It is 2017, LED lighting is now affordable and reliable, and CFLs are all but gone. Along with the 50-75% energy savings when compared to traditional lighting, LED lamps last longer! The avoided cost of ongoing lamp purchases and labor, along with available utility rebates (i.e., typically 20-75% of retrofit costs) will further strengthen the business case.

In the age of the Internet of Things, lighting control options are plentiful. From simple wall-mounted occupancy sensors to networked lighting control systems, controllability options and costs vary significantly. However, the business case for lighting controls can be quite compelling considering 20-40% of a building’s energy consumption is associated with lighting. Once again, if it does not need to be on, turn it off!
(Typical payback period: 6 months-3 years; Application: All building types)

10. High efficiency motors and drives. Fan and pump motors are likely some of the largest energy consumers in your building. When compared to standard efficiency motors, high efficiency models consume approximately 2-8% less energy and high efficiency variable frequency drives (VFDs) can reduce motor energy consumption by 20-40%. And most utilities offer rebates for high efficiency motors and drives. While the payback period for these technologies is longer, the impact on your balance sheet will be quite large.
(Typical payback period: 1-4 years; Application: All building types)