A Guide for Hotels: Boosting Profits with Energy Efficiency & Conservation

Distributed Generation

Like any business, hotels have the opportunity to reduce energy use and energy costs by generating their own power. With recent technological advancements, the opportunities are continually increasing.

Hotels in locations with the proper natural conditions may be able to take advantage of solar power to meet some of their energy needs. Solar energy is an especially good choice for hotels in hot, sunny climates, such as Southern California and the Central Valley. In these areas, the hot sunny summer weather means that the peak periods for energy use often coincide with the peak conditions for producing solar power. A hotel solar system will save electricity during the most expensive times and will help protect the power grid by lowering the impact of high cooling loads. The large rooftop surfaces of suburban and rural hotel buildings provide ample space for a solar system, and systems can be easily tailored to meet specific needs. Consider installing a system in conjunction with a cool roof and increased insulation. Increased rebates and incentives in California and other states make this the opportune time to consider solar power for your hotel. Hotels can also opt for a Power Purchasing Agreement, a less capital-intensive route to getting solar on your roof. Talk to your local solar installer about incentives, rebates and other financing options.

Cogeneration, or combined heat and power (CHP), is another good option for large hotel properties. A CHP system consists of an engine, turbine or fuel cell (prime mover) that generates on-site electricity, plus a heat recovery unit that captures waste heat from the generation process. In large hotels, CHP systems are usually connected to an absorption chiller that provides heating and cooling for the HVAC system. The absorption chiller - powered by thermal energy - replaces a traditional chiller powered by electricity. Cogeneration systems can also heat domestic water for use in the building.

Absorption chillers, although technically part of the HVAC system, are fueled by low-grade waste heat recovered from on-site electricity generation. Absorption chillers are available in capacities ranging from 100 to 1,500 tons and use environmentally benign refrigerants and absorbents instead of polluting chlorofluorocarbons. Although absorption chillers have a low coefficient of performance when compared to electrical chillers, they are extremely cost-effective and efficient when used with a cogeneration system, since very little electricity is used to power the chiller. Consider that the cost of cooling is about 22%of a building's total electrical expenses - the savings become clear.

Leading by Example: Hilton Palm Springs

The Hilton Palm Springs has been an efficiency leader for years, employing an energy management system and undertaking many efficiency actions. The hotel further cut power use by installing solar water heaters for the 110,000-gallon swimming pool and installing two 140-kW cogeneration units with 50-ton absorption chillers to generate peak power. The chiller optimizer alone saves $36,000 annually.