The estimated 45 million existing commercial buildings in the U.S. contain far more potential to deliver real energy savings and reduce global warming than new buildings ever can, simply because they represent the overwhelming majority of commercial U.S. properties.
LEED for Existing Buildings (LEED-EB v2.0) provides owners with the benchmark and verification data needed to act. Improved performance can be realized immediately using a low-cost or no-cost approach. So, why wait to gain the benefits of sustainability in existing buildings? Here are six high-return initiatives for greening existing buildings:
1) Identify and Fix Energy Hogs — Establish a cross-disciplinary “green team” to investigate and establish the current carbon footprint for every existing building. Look for and address the low hanging fruit. In many workplaces, especially those with research, data storage, computer-aided design, and lab functions, technology equipment consumes enormous amounts of electricity. Basic modifications can go a long way to reduce electrical demand. Purchase ENERGY STAR-rated equipment when replacing older models. Investigate how to qualify for utility-sponsored incentives and rebate programs.
2) Rethink Lighting — Few companies take advantage of emerging lighting strategies and technologies. New LED lighting options present opportunities to save up to 70 percent when used in task lighting and exterior lighting, and new interior lighting fixtures are now available. New overhead lighting alternatives are far more efficient than standard parabolics. Occupancy sensors and watt stoppers will produce dramatic savings for a low upfront cost. Challenge the perception held by many facility managers about the need for a large volume of overhead lighting by using more task lighting and daylighting, and you will significantly reduce energy bills and improve employee comfort and productivity.
3) Review Water and Wastewater Use — One of the most tangible opportunities within existing buildings is in water and wastewater management. On the water side, smart industrial owners are implementing innovative recharge and reuse technologies including today’s improved Reverse Osmosis and DeIonization (RO/DI) systems. The result is dramatic reductions in potable water requirements and wastewater discharge. Office buildings and corporate campus sites can cut water use by installing low-flow fixtures, reviewing outside irrigation demand, and planting hardy ground cover in place of lawns.
4) Reduce Heating and Cooling Cost — The greatest long-term savings can be achieved by studying heating and cooling systems and improving HVAC system efficiency. Start by examining existing equipment. Retro-commissioning is advised for best efficiency practices on existing systems. A commissioning agent will balance and tune the system’s components to optimize savings. Implement preventative maintenance for every building fan system, with airflow measuring stations to track intake and exhaust. An air flow imbalance is common with older equipment, often drawing 50 percent more outside air exchange than needed. Install heat recovery systems, if applicable, and reduce peak load demand. If possible, reduce the heat island effect on rooftops through use of cool roofing with highly reflective materials or vegetated roofs.
5) Investigate Renewable and Alternative Energy Sources — Existing buildings are prime candidates for alternative energy strategies. Many companies are purchasing renewable energy credits or exploring the use of photovoltaic, passive solar, passive cooling, solar thermal, geothermal, bio-fuels and wind power technologies. The feasibility of these options depends on such factors as geographic location, climate, size of the company, and acceptable payback scenarios for investing in alternatives.
6) Consider Renovation and Fit-up Changes — Commercial office buildings, where demolition and tenant fit-up are frequent, produce an enormous amount of construction waste. With an aggressive and uniform program for construction waste management, reductions of 30 to 60 percent in waste-to-landfill can be achieved. We find that many items that traditionally end up as demolition waste can be reused as part of the new space. Reducing landfill and transport costs can deliver significant annual savings, and reduce the construction cost of every project — large and small.
As you consider the timing for a green program for existing buildings, examine all your options and focus on areas of highest return on investment and reputation. With new urgencies in play, the question shifts from when you should act to what are the consequences of waiting.
