8.2.2

8.2.2 Energy Conservation

Energy conservation is an important concern when new facilities are constructed on Fort Carson. The building design is the key component in determining energy impact on Fort Carson for years to come and is discussed in depth in Appendix D. However, some other factors that have long term energy impacts to Fort Carson need to be addressed and considered when constructing or renovating on Fort Carson.

This section contains established energy conservation design standards for new construction, major renovation projects, minor repair projects, and energy conservation projects for facilities on or operated by Fort Carson. These standards are in response to Federal law, Presidential Executive Orders, Department of Defense requirements, and HQ Installation Management Agency goals and requirements.

Designs will include all practical energy and water conservation measures determined to be life cycle cost effective. Points of contact for energy conservation can be found in Appendix B.

8.2.2.1 Energy Use Budget

According to the Energy Policy Act of 2005, all new Federal facilities must be designed to achieve energy consumption levels 30% below ASHRAE design standards, and sustainable design principles must be applied to the siting, design, and construction of new and replacement buildings.

The Energy Use Budget (EUB) is a key component to determining compliance with the Energy Policy Act. The EUB is the maximum building energy use (as stated above, 30% below ASHRAE design standards) for which the building is to be designed. The EUB is expressed in MMBtu/kSf per year. A check must be conducted by the design agent to verify that the Design Energy Usage (DEU) is within the EUB. The DEU is defined as the computed annual energy usage of a proposed building design based on normal loads for maintaining comfort and amenities for the occupants. Energy gained within the space of a building, resulting from process energy loads, may not be used in the calculation of the DEU to facilitate the verification of the DEU within the EUB.

All energy calculations for any new building that is heated only or heated and/or air conditioned and exceeds 3,000 square feet of gross floor area will be calculated using a professionally recognized and proven computer program or programs that integrate architectural features with air conditioning, heating, lighting, and other energy producing or consuming systems. These programs will be capable of simulating the features, systems, and thermal loads used in the design. Using established weather data files, the program will perform 8760 hourly calculations; a calculation for each hour in a year. The Building Load Analysis and Systems Thermodynamics (BLAST), DOE 2.1E, and BESA (Canada) energy analysis programs are recognized as acceptable programs for these purposes. BLAST is preferred by Fort Carson and the USACE. Programs that "condense" the weather files and number of calculations into several "typical" or average days per month or follow modified bin calculation procedures may not be used for analysis of Fort Carson designs. An adequate design analysis requires the input of detailed data about the building envelope, interior loads, weather, energy systems, etc., and perform hour-by-hour calculations of energy consumption over the entire average year.

8.2.2.2 Life Cycle Cost Analysis and assessment

Design agents will consider all reasonable approaches for providing the proposed facility with its required energy and then use life cycling costing analyses to determine which systems should be used based on lowest life cycle cost.

The energy to be considered will include all known thermal loads including process, ventilation, and occupant loads. Operating hours will be those actually anticipated for operation. Special attention will be given to ensure that all feasible energy and water conservation alternatives, including renewable energy systems, are included in the analysis. The results of the Life Cycle Cost Analysis or LCCA will be the determinant in system selection instead of initial acquisition costs.

LCCA methods must average facility energy loads as a function of time-of-day for each week of the year. The time-of-day detail is required when the cost of energy, such as electricity, varies over the 24-hour day and also contributes to special charges such as demand charges. Using these average weekly time-of-day consumption estimates, current rate schedules, and approved rate escalation estimates, along with projected operation and maintenance labor, parts, and supply costs, equipment efficiencies, and major overhaul costs, projected life cycle costs for competing energy are developed.

In all cases, the essential elements of the design selection process including, as a minimum, the basis for which the list of feasible alternatives was developed and the basis upon which the various design decisions were reached, will be documented in the design analysis, retained in the project file, and made available to Fort Carson upon request.

A Life Cycle Cost Assessment should be done in conjunction with the Life Cycle Cost Analysis but should encompass more than the evaluation of the various systems being used for a new facility. This assessment should address externalities related to the sustainability of the facility such as a whole-system assessment of the raw materials being incorporated. How are they produced, harvested, manufactured, and distributed as well as how the material effects the sustainability of the facility throughout its entire life and how recyclable the material is at the end.

8.2.2.3 Energy Consuming Equipment Efficiency

All energy consuming equipment will be specified to ensure efficiencies are of the highest extent that is life cycle cost effective. Energy Star rated equipment (motors, boilers, furnaces, etc.) and building materials (windows, insulation, etc.) is highly encouraged due to its assurance that the equipment and materials are of the highest efficiency as certified by the EPA.

8.2.2.4 Energy Control and Monitoring

Utility Control Systems, (UCS) are installed or planned for all of the facilities at Fort Carson. New buildings or major renovations will include UCS. UCS will be designed to be compatible with and connected to existing or planned central control systems. Information on the current UCS is available from DPW. See Appendix B for more information

8.2.2.5 Special Energy Considerations

Described in more detail in Appendix D, other passive features and techniques are quite practical as Fort Carson focuses on energy efficiency. All of these systems, features, and techniques will be evaluated for possible inclusion in the design of new or renovated facilities.

8.2.2.5.1 Passive Solar Desings

passive solar designs

The local climate at Fort Carson, with its extensive heating season accompanied by substantial solar insolation, makes it an ideal location for employing passive solar designs. Numerous studies and actual measurements of passive solar buildings have consistently shown reductions in energy consumption of thirty to fifty percent when compared to similar buildings of conventional design. When these features are incorporated into the initial design, they can be very cost effective. Designers will consider passive solar systems, hybrid or combined passive and active solar systems, and other solar systems that can be reasonably evaluated and that are practicable as well as life cycle cost effective for every new facility and major renovation at Fort Carson. Key features of a passive solar design are:

Proper building orientation to collect the maximum amount of solar energy during the winter months. Facilities should have a predominant southern exposure and elongated easy-west configuration.

Substantial areas of south facing windows and clerestories to collect large amounts of solar energy during the winter months with overhanging roof eaves to shield these windows and clerestories during the summer months.

Use large amounts of massive materials (masonry, concrete, etc.) on the inside of the building to store the solar thermal energy let in through the windows. The massive materials should be accompanied by thick insulation on the outside to prevent the collected thermal energy from escaping.

Easily operated control devices (window shades, insulated window blinds, shutters, dual-pane windows, etc.) to permit collecting of solar thermal energy when desired and prevent its loss out of the building during the night.

8.2.2.5.2 Solar Preheating of Water

Many facilities at Fort Carson require large quantities of domestic hot water (DHW) and thus consume large quantities of thermal energy. These facilities warrant serious evaluation of the possible use of active solar preheating of DHW. Additional funding required for an active solar water pre-heating system will be listed as a separate line item on the concept cost estimate. Based on this estimate, a life cycle cost analysis will be conducted. If the life cycle cost analysis proves the solar system to be cost effective, it will be included in the design.

8.2.2.5.3 Transpired Solar Collectors

Transpiration heating using perforated metal panels to extract a flow of boundary layer heated air has shown to be highly cost effective when implemented at numerous industrial plants where a large flow of heated ventilation air is required to meet safety and health standards in buildings with high levels of fumes from volatile materials (fuels, greases, cleaning fluids, etc.). New construction and major renovation of vehicle and aviation maintenance facilities at Fort Carson that require large amounts of heated ventilation air will be analyzed for the application of transpiration heating. This feature should be included in the design if life cycle cost analysis proves this system can be effective.

8.2.2.5.4 Evaporative or Indirect Cooling

The relatively dry summer climate and short cooling season makes evaporative or indirect cooling a very workable and cost effective option for space cooling at Fort Carson. Current technology provides high efficiency evaporative cooling systems which, combined with natural ventilation, can effectively provide cooling for a wide range of facilities. With proper maintenance, evaporative cooling offers no special health concerns. Evaporative cooling will be considered for all new major renovation facilities at Fort Carson and, if appropriate and cost effective, will be included in the design.