Preliminary Recommendations for Energy Savings For Galloway

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Preliminary Recommendations for Energy Savings
For
Galloway Township Municipal Facilities
A preliminary assessment of the Galloway municipal facilities’ main building and post office building were
conducted in March/April 2007 by an undergraduate team of the Richard Stockton College of New Jersey’s
Environmental Studies and Political Science program in Sustainability and Environmental Policy. Students
worked under the supervision of Professors Patrick Hossay and Tait Chirenje.
The following are preliminary ‘low hanging fruit’ that can help improve the energy performance of the
building and reduce its environmental impact of its operation. We have limited our recommendations, at
this preliminary juncture, to those that have a cost of less than $2500 and a clear savings payback within
2.5 years.
We are now in the process of completing the computer simulation of the building’s performance. After the
completion this analysis, we will be able to suggest and better quantify more significant changes in
operation and maintenance, if needed.
If desired, student teams will be able to conduct the following tests and analysis in the Fall: (1) A
pressurized thermographic analysis of the facility; (2) data loggers may be used to evaluate energy use in
operations, policies, and management practices; (3) a rainwater management and pollution assessment,
including the potential use of rain gardens and integrated pest management.
Overall, the building was found to be well managed. The operations and maintenance staff is clearly
knowledgeable and has adopted several energy saving procedures. Hence, these recommendations may
serve to improve what is already a well maintained facility.
Lighting
Replace all incandescent lights with compact florescent lighting.
Compact florescent floodlights should be placed in all appropriate fixtures that now utilize incandescent
bulbs. Current 40 watt bulbs can reduce their energy use to 15 watts with the same light output.
While precise cost savings is dependent on use patterns, which has not yet been measured, our estimates
indicate that the replacement of the incandescent bulbs with CFLs can save $1,607 over the life of the bulbs
and prevent the discharge of 10,256 pounds of CO2.
Cost: $487 for replacement of major incandescent bulbs in facility. Energy savings will exceed cost of new
bulbs in eight month.
Utilize photoelectric controls in common areas that have daylighting
Common areas of the main facility, including the two major entrances and the corridor on the buildings
north side, offer substantial daylighting opportunity. On a normally lighted day, available daylight in these
spaces was measured at 180 foot-candles. Twenty foot-candles, or about ten percent of the current lighting
level, is considered adequate ambient lighting. Nevertheless, five of seven spot checks indicated that
interior electric lights in these areas are often left on when incoming daylight is more than adequate to light
the spaces.
A more systematic effort to keep these lights off during adequate daylight periods would help. But, because
the building is dark in the winter mornings, staff will be likely to turn the light on most mornings of the
year. Once turned on, it is likely that they will remain on for the duration of the day.
Photoelectric sensors and controls can reduce this unnecessary consumption by turning off or dimming
lights automatically depending on natural light levels. These sensors monitor available light and regulate
the output of electric lighting. Most inexpensive photosensors use cadmium sulfide as the active element
for light detection. Electronic photosensors use a light sensitive silicon diode to detect daylight and provide
more precise control. Electronic photosensors are more costly than cadmium sulfide cells but savings in
energy costs generally justify their installation.
Cost: This measure would be too costly to install as a stand-alone retrofit. However, as part of an overall
lighting update to the facility, this feature would add an additional $980 in cost. This measure will reduce
annual energy cost by $386 if utilize only in the three identified common areas. Hence payback will be
achieved in roughly 30 months.
Reduce total luminescence and thus wattage in over-lighted areas
Ambient lighting in common areas should be maintained at about 20 foot-candles. For computer use, about
30-50 foot-candles of light is needed. And, only when the most detailed design work is being completed,
such as paper drafting and design, should lighting exceed 100 foot-candles. While lighting in main offices
was adequate, in several spaces, electric lighting was clearly excessive. This waste energy and can result in
glare on computer screen as well as potential negative physiological (I thought it was just psychological?)
symptoms among office staff. Several offices, copy room, bathrooms, and workspaces registered lighting
levels of 55-90 foot-candles. Overall, a mean 28% excess lighting in 23 percent of administrative floor
space was identified.
Because many rooms are lighted excessively, consider 25W T8 lamp instead of a 32W T8 lamp in
compatible fixtures. In older fixtures consider the use of dummy florescent tubes to reduce energy use
while maintaining evenness of lighting. A better solution would be an overall lighting update (see next
recommendation).
Consider an overall lighting update
Much of the lighting in the main facility is poorly balanced and inefficient. Consider upgrade to digital
electronic dimming ballasts, controls, and environmental sensors in all building areas that have not been
updated.
This should include the replacement of all magnetic ballast. Ballasts provide a controlled current to the
fluorescent tubes. However, about 25% of the population is sensitive to ballast flicker and hum and actually
can become physically ill from too much exposure to it. An easy solution is to upgrade ballasts to solidstate electronic ballast. They are lightweight, generate very little heat (thus saving on cooling cost), and
operate at about 25,000Hz (cycles per second), rather than the standard 60Hz used by the old systems and
thus effectively eliminate all flicker and hum. When switching to these ballasts, it is also necessary to
change to T-8 fluorescent tubes, which are available in a full-spectrum type – providing excellent, daylightlike color rendering (25W T8 would be an economic choice). Ensure that lighting contractors recognize
your desire to avoid over lighting.
These electronic ballasts offer long life and energy savings, providing a 30% reduction in energy
consumption. Coupled with potential NJ state clean energy rebates, makes upgrading all ballasts a very cost
effective and environmentally sound option.
Cost: Combined with photoelectric daylighting controls in common areas, this changes can generate total
energy savings of 50% to 70%, increase occupant comfort, and increase space flexibility. Conservative
preliminary estimates of savings are $1767 annually. Facility electric bills will be required for more precise
estimates. However, upgrades in similar buildings generally deliver a less than 3 year payback and an
attractive 50 percent or more return on investment.
Basement lighting
There is a high probability that basement lights are left on when the space is unoccupied. However, until
the data logging procedures are complete, we cannot provide supporting evidence for this suspicion.
Several solutions may be used to address this problem in part or in whole. Signage may be added to the
exits, reminding staff to turn out lights. Occupancy sensors would be an ideal solution. But the cost would
be high, given the large space and complexity of the storage area. A general overall light with limited
output combined with localized lighting on timers may also help address this problem at lower cost.
Heating/Cooling
Install ceiling fans in courtroom
Staff reports and on-site measurement indicate that the courtroom is notably uncomfortable when fully
occupied. The vertical temperature vatiation in the courtroom when unoccupied was found to exceed 13
degrees Fahrenheit, indicating the potential for greater energy efficiency with proper air circulation. A
ceiling fan would help reduce heating and cooling cost for this space and provide a more comfortable and
even temperature and humidity. Two 40-55 inch, reversible, energy-star fans are recommended to produce
minimal air flow required.
Cost: Operation of these fans will result in a 26 percent decrease in total heating and cooling energy. When
the probable energy use of the fans is incorporated, an overall savings of 18 percent is estimated. Cost of
installation will vary with the wiring requirements of the room; but should be relatively inexpensive given
the existing wiring for lighting.
Courtroom temperature management
The courtroom is heated and cooled throughout the week, although it is only used on two scheduled days.
Staff report that the room is sometimes used unexpectedly and thus needs to be maintained at a comfortable
temperature. We recommend that the thermostat be programmed to maintain the room at 62 in the winter
and 78 in the summer. On scheduled use days, the program can be maintained at present settings. This will
reduce energy needs for the majority of the week while maintaining a room temperature that will allow use
for unscheduled events.
Cost: No cost. Energy savings cannot be precisely calculated without a full building simulation, but we
now estimate it to be $932 annually.
Retard air movement through abandoned elevator shaft
This elevator shaft is responsible for significant unwanted air movement and heat loss. Normally, such a
shaft should be sealed. But, since this shaft is still utilized to move large items, a movable barrier should be
installed to inhibit air movement. As this is not a public space, simple double plywood doors could be built
to close the basement area off from the shaft when not in use.
Cost: estimated energy savings is $360 annually. Cost of materials is roughly $230.
Heat loss through the elevator shaft is evident in this thermographic image.
Uninsulated ductwork outside the building insulated envelope can lead to considerable energy loss.
Insulate ductwork in unconditioned space
Much of the ductwork for the main facility is in the unconditioned attic. This is a source of considerable
energy loss. As these thermographic images suggest, additional insulation around existing ductwork will
dramatically reduce losses.
Cost: $1300 with labor, $250 for materials. Energy savings will exceed $670 annually and provide more
balanced heating and cooling for the building.
Consider heat recovery ventilator or air exchanger for basement ventilation system.
Significant heat loss is occurring from what is otherwise a well-designed and effective basement ventilation
system. Thermographic imaging in summer and winter indicate a significant loss of energy. A recovery
ventilator will allow for continuous or intermittent fresh air to the basement while reducing energy loss
significantly. These ventilators can provide up to 250 cfm of ventilation while preheating or precooling
incoming air.
Alternatively, an air exchanger may be used if ventilation requirements are modest. In this system,
incoming air is tempered as a result of being tumbled with the inside air prior to delivery. There is no heat
recovery core. Up to 2000 square feet may be ventilated with this more modest and inexpensive system.
Cost: $310-$1067 for equipment. Computer simulation must be completed before a precise cost savings
may be calculated, but payback is expected to be achieved in less than 24 months.
Significant temperature variation in and out flow pipes indicate the potential savings from heat recovery/
Building Envelope
Repair and augment insulation in main building
The damage to the insulation in the main building is significant and the cause of major energy loss. Major
tears and missing insulation should be repaired as soon as possible. In addition, a well maintained vapor
barrier can help prevent infiltration and exhilaration of air in building and result in significant reduction in
heating and cooling cost.
As these thermographic images suggest, the energy loss through these holes in the insulation are major
sources of energy loss. Existing R value of portions of the roof is R 5. Recommended ceiling insulation in
New Jersey is R 49.
Augmenting the current insulation with an additional layer of even R11 would reduce your heat loss in this
space by 40 percent. Hardboard insulation could be installed at relatively little cost.
Cost: $50 in materials for repairs. Energy loss and thus cost of inaction is very high. Payback will be
achieved in less than 3 months.
Compromised insulation in attic is source of significant loss.
Even small holed can lead to significant losses
Augment insulation in post office basement.
The post office building basement was found to be maintained as an unconditioned space. In fact, basement
windows are left open in the winter. However, because of inadequate insulation, the result is significant
energy loss. A computer simulation will allow us to quantify this loss; but it is already clear that additional
insulation is called for and will provide a probable payback period of less than three years. Alternatively,
the basement could be brought into the building envelope.
Cost: not yet determined.
Insulation is missing from several areas of main and post office building attic and basement.
Thermographic imaging also identified several old light fixtures, in serious disrepair, that are still
connected to hot wires. These should be shut off if possible to avoid a fire hazard. This light fixture is in the
second room of the main building’s attic and is unusable.
Utilize energy saving window treatments
A variety of translucent shades are available, including some that can be motorized or automated, if
desired. North facing windows may be fitted with an insulating shade, such as a double honeycomb design
with an R value of 5.5. This could help reduce energy loss through windows. South facing windows may be
fitted with similar treatments, or window blinds if preferred, to minimize solar gain and localized
overheating in summer months.
Cost: Total cost depends on the extent and type of installation. A normal office window sized double
honeycomb blind cost approximately $50-$80. Total savings will be calculated with the completion of the
computer simulation; but payback period is likely to be 18-36 months.
Water management
Insulate water pipes in post office building, or shutdown water heater
If hot water is not needed in post office building, shut down water heater. If it is determined that hot water
is needed, insulation of hot water pipes can help save energy and water when hot water is utilized.
Cost: Shutdown has no cost. Insulation cost estimated at $79 with labor.
Consider the use of rain gardens
Over one million gallons of rainwater runs off the municipal complex roof each year. Such runoff
contributes to serious environmental challenges in the area. A simple yet effective solution would be the
use of rain gardens to intercept some of this runoff. Raingardens are low areas where storm water is
captured and infiltrated into the ground. Layers of soil, sand, and mulch are planted with species that will
help maximize infiltration. These gardens can be quite attractive, enhancing the appeal of the facility.
Several areas of the facility would be appropriate, including areas between the sidewalk and the street, near
downspouts (but at least 30 feet from building), or adjacent to hardscape.
Cost: With community (or student) volunteer labor, raingardens need not cost much. Typical cost is $3 per
square foot. There is no payback period.
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