Please Note: This proposal is not intended as a formal paper and is more akin to a rough draft. All numbers used are estimates using anecdotal evidence that was available during the Save Award submission period.
This proposal addresses two usages of power with the potential for significant savings in energy and government costs with minimal cost of implementation. Simple estimation techniques are applied from observed behaviors at one NASA center to derive an estimated monetary savings across the federal government. The total estimated savings exceeds one billion dollars per year. The policy implementation required to realize this savings is simple: require building and facility managements to require employees to turn off unnecessary lighting and computer monitors when leaving their facilities.
The first case of power usage that could realize significant savings is hallway lighting. Although motion sensors are planned as mentioned on SaveAward.gov, there are significant start-up costs and infrastructure construction required for such a plan. Currently at NASA Ames, many fluorescent lighting fixtures in hallways are left on every night and on weekends. On average, each fixture contains three 33 watt (W) fluorescent lights for a total of 99 W per fixture, although some building managements have taken the initiative to reduce this lighting to 33 W per fixture or 1 fluorescent light per fixture; for the purposes of underestimation this proposal will assume 33 W per fixture. In one building at NASA Ames estimated to be an average size for the center, there are at least 90 fluorescent fixtures on the 2nd floor and about the same on the 1st floor used for hallway lighting; lighting in the hangar area, offices, cubical areas, and 3rd floor are not included in these numbers. These numbers puts the estimated power lighting the hallways at 5940 W for an average sized building at NASA Ames.
Assuming 10 hours per weekday and 48 hours per weekend there is no need for hallway lighting, often times there is more than 10 hours per weekday without this need, then there is a total of 98 hours per week when hallway lighting is not needed. Using the above 5.940 kilowatts (kW) required for lighting the hallways at 98 hours per week gives an estimated 582.120 kilowatt-hours (kWh) of energy used that is not required. At 10 cents per kWh, which is less than PG&E’s advertised average rates of 12 to 13 cents per kWh, this would amount to $3026.92 per year in unnecessary hallway lighting in one building of average size at NASA Ames; this amount was derived in an attempt to underestimate the amount and cost of hallway lighting.
While $3026.92 per year, rounded to $3000 per year for remaining calculations, might not seem like a lot of savings, there are over 50 buildings at NASA Ames. If the above building is an average case for hallway lighting, many buildings at NASA Ames use more hallway lighting, approximately $150,000 per year could be saved across the center. If NASA Ames is an average case for the amount of hallway lighting per center, then across the 10 major NASA centers a savings of $1.5 million per year could be realized by turning of the light switch when hallway lighting is unnecessary.
If the amount of unnecessary hallway lighting per NASA employee is equivalent to the amount of unnecessary hallway lighting per federal employee, then an extension of this estimate can be made to all federal buildings. The National Academies Press estimates the number of NASA employees to be over 17,000 and the Washington Post reports that the number of federal employees is approximately 14.6 million, giving a ratio of 858.8 federal employees per NASA employee. Applying this ratio derives a federal-wide estimated monetary savings from unnecessary hallway lighting of $1.289 billion in savings per year.
The second usage of power where significant savings could potentially be achieved is computer monitors. Often times, NASA employees leave their monitors running a screensaver overnight and on weekends, not taking advantage of the power saving settings offered by modern operating systems. Estimates of the NASA civil workforce, which does not include on-site contractors, put the number of NASA employees at about 17,000, with a larger number of on-site contractors, thereby providing an underestimate of the number of employees on-site at NASA. Assuming that employees only need to use their computers 10 hours per weekday and not at all on weekends, then there is 14 hours per weekday and 48 hours per weekend when their computer monitor does not need to be on and can be powered down. This totals to 118 hours per week of unnecessary time that the computer monitor is on.
Many estimates put the actual power usage of a 17” CRT monitor at about 70 W and a 17” LCD at about 20 W, although the manufacturer power usage ratings are much higher. The majority of monitors at NASA Ames are 17” and larger LCD monitors and it will be assumed all agency computers are 17” LCD monitors for estimation purposes. Assuming that about 90% of employees do turn their monitors off, which appears close to the actual from anecdotal evidence, then only an estimated 1,700 employees leave their monitors on at night. Using the estimates of 118 hours per week an employee is not at work, 20 W per 17” LCD monitor, and 1,700 employees that leave their monitor on, then an estimated total of 4,012 kilowatt-hours could be saved per week at NASA across all centers.
PG&E’s advertised average rate of power is more than 12 cents per kilowatt-hour. Using 10 cents per kilowatt-hour as an underestimate, $401.20 could be potentially be saved per week, or $20,862.40 per year. That may not seem like a large number, but if the same ratio of 858.8 federal employees per NASA employee is applied in the same manner as with the unnecessary hallway lighting, then the savings federal-wide would amount to an estimated $17.9 million per year. Please note, the estimate of cost savings could be increased if computers are shut-down as well.
An estimation of monetary savings from a simple policy implementation is proposed. The policy implementation is to require building and facility managements to require employees to turn off unnecessary hallway lighting and computer monitors when leaving their facilities for nights and weekends. An average sized building at NASA Ames is used for observation and an estimate of the power usage and cost savings due to hallway lighting and computer monitors is made. Simple estimation techniques are then used to extend this estimated savings first to all NASA centers, then across the federal government. This estimate shows that a potential $1.306 billion could be saved per year federal-wide. While the estimation techniques in this proposal are not precise, they are close enough approximations to indicate further analysis should be required to accurately quantify the cost-savings.