improvements made at the CPP. This is typical of experiences on large institutional campuses in the United States where investments in district energy systems similar to that serving the U.S. Capitol Complex have provided efficiency improvements greater than those realized through improvements in the buildings on the campuses that are served. However, recent and proposed legislation coupled with activities such as the “Green the Capitol Initiative” (Beard, 2007) now require further attention to energy efficiency and reduction of greenhouse gas emissions.

Consulting Services

The committee was impressed with the number of options considered for the CPP and the routing of the distribution system in the 70% Report. The consulting teams demonstrated considerable knowledge and experience in the types of systems that exist to serve the U.S. Capitol Complex and the current and viable technologies for the energy infrastructures of the future.

The AOC staff directed the consultants to evaluate the potential impact of pending greenhouse gas (GHG) emissions regulations on the cost-benefit analysis of the options. The committee believes it is highly likely that GHG emissions legislation/regulation will be enacted within the life of the proposed energy infrastructure replacements; therefore this analysis is very important and probably has helped to shift the project requirements in a direction compatible with GHG regulations. In particular, it has become clear that using biomass or fuel cells as options to replace the CPP are not viable options for the near term even when the potential impact of GHG legislation is considered. In addition, in response to a request by the committee, a thorough CO2 accounting was added to the 70% Report.

In the 70% Report, consideration has been given to viable energy distribution tunnel rehabilitation and steam and chilled water line routing options, as well as options for multiple central plants and stand-alone equipment located closer to the buildings being served. Multiple paths for the distribution systems were developed and analyzed, as were the possible reuse and the replacement of the existing tunnels. For replacement options, new tunnels, direct buried piping, and covered trenches have been thoroughly evaluated.

Consultants’ Report

The AOC specifically requested that the committee act as a second-level reality check against fatal flaws in the AOC methodology or strategic development. Within the parameters of the 70% Report, the committee did not find any fatal flaws in the analyses presented.


This section describes the shortcomings identified by the committee in the presentations at the workshop and in the 70% Report. The section that follows discusses the actions that the committee recommends be taken as the Strategic Long Term Energy Plan is carried from 70% to 100 percent completion, to overcome some of the identified shortcomings. Other shortcomings described in this section are undoubtedly beyond the scope of this activity. They can be addressed only as part of the broader set of analyses recommended by the committee, as presented in Chapter 3.

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