Energy strategies abound for integrated buildings:Our economy and standard of living depend on an adequate, steady supply of energy; however, the U.S. Department of Energy’s (DOE) Energy Information Administration (EIA) projects steady growth in electric energy consumption through 2030 in its Annual Energy Outlook 2007. EIA forecasts total electric energy use in the United States will increase at an average annual rate of 1.5 percent per year over the next 24 years—a total of about 43 percent by 2030.
The commercial sector—office buildings, schools, hospitals and similar types of buildings—is projected to increase at a rate of 2 percent per year for a total of about 61 percent over the next 24 years. Similarly, the EIA predicts residential energy use to increase at a rate of 1.3 percent per year for a total increase of 36 percent over the study period. As expected, electric energy use in the industrial sector is only projected to increase by 0.6 percent per year or about 15 percent through 2030, due to reduced industrial output in the United States.
A large portion of the electricity use growth is due to increased use of information technology in both the workplace and at home. This equates to opportunities for electrical contracting firms that have expertise in either or both renewable energy sources and integrated building systems (IBS).
The United States has experienced an increasing demand for electric energy since its commercialization more than a century ago. In the past, this increased demand was met by building more and bigger power plants and associated transmission lines. Regulatory changes, environmental regulations, economics and public concerns made building new coal-fired and nuclear power plants and transmission capacity increasingly difficult, if not impossible, in some parts of the country. Over the past 20 years, utilities have increasingly relied on packaged combustion turbine units that are fueled by natural gas to meet growing demand.
These units can be easily sited at or near urban load centers, eliminate the need for new lines, and use natural gas that is relatively clean. However, over the past several years, the cost of natural gas has risen substantially with global demand, while environmental concerns over fossil fuel use have made these units less attractive. While new power plants are needed in the coming decades, this is only part of the solution. Renewable energy sources and increased building efficiency will both be important in preserving both U.S. energy security and the environment.
Renewable energy sources include photovoltaics (PV), wind, geothermal, hydro, biomass, and other similar environmentally friendly technologies. Utilities and independent power producers (IPPs) are building large-scale renewable energy installations in response to federal, state and local incentives and subsidies, requirements that a certain portion of a utility’s generation mix be from renewable energy sources, or public demand for renewable energy.
Facility owners and operators that want to have all or a portion of their electric energy needs supplied from renewable sources don’t have to be connected directly to a utility that has renewable energy capacity. Instead, a renewable electric energy supply can be met through the purchase of tradable renewable certificates (TRCs). The utility or IPP that is generating electric energy from renewable sources sells that electricity to its customers at its normal rate. It then makes up the difference in cost between producing the renewable energy and conventional fossil fuel generation by selling TRCs to facility owners or operators. Not only do TRCs give facility owners and operators access to renewable energy sources that they might not have otherwise, but they also provide an incentive for utilities and IPPs to build renewable energy sources because TRCs create a wider market for green power than might exist in the utility’s or IPP’s service area.
In addition to utility-supplied green power, commercial buildings can produce their own by installing PV panels or other renewables. Today, most states and utilities support net metering, which allows excess energy produced by the facility’s PV installation to flow into the grid. When the facility operates at an energy deficit, it draws needed energy from the utility grid. In effect, net metering allows the utility grid to be used to store excess energy produced by the facility’s PV system until it is needed.
High-performance buildings (HPBs) are as much about IBS as they are about the use of energy efficiency. HPBs achieve very high efficiencies when compared to traditional buildings by optimizing the entire building as a system rather than trying to optimize individual systems, such as lighting, HVAC, and others. These buildings integrate daylighting, solar heating, and fee cooling with the building’s artificial lighting and HVAC systems using advanced controls that attempt to maximize occupant comfort and minimize facility energy costs. Not only do HPBs result in lower operating costs when energy costs are skyrocketing but they also result in greater occupant satisfaction and productivity. EC
This article is the result of a research project sponsored by ELECTRI International Inc. Glavinich is an associate professor in the Department of Civil, Environmental and Architectural Engineering at The University of Kansas. He can be reached at 785.864.3435 or email@example.com.