"Reducing Electric Energy Operating Expenses at Montana de Luz
Spring Break 2009
Engineering 692
Prepared by: Engineers for Community Service (ECOS) College of Engineering The Ohio State University
April 17, 2009
Students: Jessica Burk, Electrical Engineering Robert Kapaku, Mechanical Engineering Stephen Marks, Industrial and Systems Engineering Lisa Reisenauer, Chemical Engineering
Faculty Advisors: John Merrill, College of Engineering Roger Dzwonczyk, Electrical Engineering
Contents
List of Figures ................................................................................................................................................ ii List of Tables ................................................................................................................................................ iii Introduction .................................................................................................................................................. 1 Project planning and analysis ....................................................................................................................... 1 Materials budget ........................................................................................................................................... 2 Interactions with ENEE and Analysis of Electric Bills .................................................................................... 2 Defective TED ................................................................................................................................................ 5 Variable Frequency Drive and Transfer Switch Installation .......................................................................... 5 Energy Audit .................................................................................................................................................. 7 T-12 to T-8 fluorescent lighting ..................................................................................................................... 9 Flashlights ................................................................................................................................................... 11 Bibliography ................................................................................................................................................ 12 Appendix A: Summary of communication needs........................................................................................ A1 Appendix B: Team’s working agreement .................................................................................................... B1 Appendix C: Kill-A-Watt Data ...................................................................................................................... C1 Appendix D: Instruction Manual for T12 to T8 Transition ..........................................................................D1 Appendix E: MdL Lighting Analyses ............................................................................................................ E1 Appendix F: Fact Finding Summary and Recommendations ...................................................................... F1
i
List of Figures
Figure 1: MdL’s historical electrical consumption by kWh ........................................................................... 3 Figure 2: Cost per kWh over time ................................................................................................................. 4 Figure 3: The final configuration of the main circuit breaker box for the MdL complex (right), and the transfer switch (bottom left) after the VFD (top left) was removed from the system................................. 5 Figure 4: The VFD (top) after it was disconnected from the circuit and the installed transfer switch. ....... 6 Figure 5: The circuit breaker box for the MdL complex................................................................................ 6 Figure 6: Kill-A-Watt EZ ................................................................................................................................. 7 Figure 7: Lowered energy costs because of increased distance between refrigerator and wall ................. 8 Figure 8: Analysis of lighting transition at this point in time ...................................................................... E1 Figure 9: Analysis of complete lighting transition....................................................................................... E2 Figure 10: Water Distribution System at MdL ............................................................................................ F2
ii
List of Tables
Table 1: Materials budget ............................................................................................................................. 2 Table 2: Useful vocabulary .......................................................................................................................... A1 Table 3: Kill-A-Watt Data............................................................................................................................. C1
iii
Introduction
Engineers for Community Service is an OSU student organization that utilizes engineering skills and technologies for local and international service projects. Its primary international work since 2005 has been in a rural region of Honduras at Montaña de Luz (MdL), an orphanage for HIV-infected children. This year our energy team focused attention on reducing MdL’s electric energy expenses. Energy consumption, in tandem with environmental issues, has become a major focus for people in all nations of the world. We took a multifaceted approach to the problem. Lighting options were an important part of our research. We developed an economic model for replacing the facility’s older fluorescent and incandescent lights with more efficient fluorescents and compact fluorescent lights. Our model estimated that this simple lighting change would reduce the total facility energy consumption by 3.5% with a 4.8 year payback on the investment. We investigated a method (variable frequency motor controller) to reduce power consumption of the electric pump that distributes water throughout the facility. We spoke with energy experts from OSU and Battelle Memorial Institute, who provided specific energy-saving suggestions as well as equipment to conduct a true electric energy audit of MdL. At the facility we initiated lighting changes in a prioritized fashion, conducted an extensive electric energy audit of MdL’s equipment and appliances, studied the effect of relocating refrigerators and freezers to better-ventilated locations and considered better lighting designs in the most-used rooms. We analyzed all monthly electric bills and correlated the results with facility usage. We met with Honduran electric energy department personnel in order to understand the national position on energy utilization. We established a set of simple recommendations that would further reduce the electric energy consumption at MdL, including implementing natural lighting solutions and re-educating MdL staff and children on energy-saving practices (practices as simple as turning off the light and fan when leaving a room). Although we found no “silver bullet” solutions for reducing electric energy consumption at the facility, we identified many small but easily implementable measures that would provide a positive cumulative effect on electric energy efficiency at the orphanage.
Project planning and analysis
Toward the beginning of Winter quarter, the Energy Team had a meeting with Vikki Rush, the director of Montaña de Luz (MdL), to determine what her needs and wants were in comparison to what the group was able and willing to do. She clearly stated that she wanted the team to find ways to lessen the electric bills at the orphanage, install solar perimeter lighting, find a way for the guards to not continually consume as many batteries, hook up a generator that had previously been donated and conduct an electrical audit of MdL.
1
The Energy Team began planning with an in-class brainstorming session modeled after the one used in November’s “World Café” discussion. Based on advice given by trip advisor Roger Dzwonczyk, the group quickly determined that solar perimeter lighting was not something we were willing to install or donate for the orphanage. After that the group conducted research on lighting individually and met with Scott Potter from the Institute for Energy and the Environment. Scott Potter informed us on what equipment we would need for our audit and gave us some tips for saving electric energy. One of his suggestions was to move the refrigerator away from the wall. From the information gathered throughout the quarter the Energy Team decided they would complete an energy audit to discover potential ways to lower energy costs, convert current fluorescent fixtures (T12s) to more efficient fixtures (T8s) in rooms used the most, convert current incandescent lights to CFLs in beneficial locations, implement a plan for future replacements of the remaining lights, explore ways of making the refrigerator more efficient, explore alternatives to traditional batteries for the guards, and meet with a representative from the electrical company (if possible).
Materials budget
The following is a materials list along with the associated cost of the items. An “x” appearing under costs denotes a donated material or material which did not need to be bought.
Table 1: Materials budget
Pre-departure
In-country
Materials CFL Lights T8 Ballasts Laptop TED Kill-A-Watt T8 Bulbs
Quantity 13 pkgs (6per pkg) 3 1 1 3 6
Cost/Unit $ 8.48 $ 29.70 x x x $ 2.43 Total Cost:
Total Cost $ 110.24 $ 89.10 x x x $ 14.58 $213.92
Interactions with ENEE and Analysis of Electric Bills
The energy team conducted a meeting with ENEE, the national electric company of Honduras, on March 23, 2009 at their office in Tegucigalpa. ENEE is nationally owned and is the sole provider of electricity for all of Honduras. The primary purpose of the meeting was to understand how MdL was being billed for their electricity, whether there were peak usage periods, and how the meter was being read. The rate for MdL’s electricity was found to be 3.7432 lempira/kW-h, which is roughly $0.19/kW-h. There is no peak period for the billing; the electricity is billed at a flat rate no matter which time of the day it is being used. The meter is not read remotely, but rather a company contracted by ENEE goes to MdL to read the meter and then prints out the bill immediately afterwards. The representatives stressed the importance of double-checking that the employee reads the meter as opposed to simply making up a number.
2
Many other insights were taken away from the meeting, as well. It was discovered there is a possibility to sell back energy, which in MdL’s case, was inquired about as a result of investigating solar energy. The sugar cane factory nearby MdL sells back electricity created by steam. In order for this to occur, an energy and environmental study needs to be conducted, and only after these are completed can a contract be drawn between MdL and ENEE. It was also discovered that there is no possibility to purchase the transformer that MdL is currently renting, and that their consumption would have to rise to 250 kW-h in order to qualify for the cheaper rate. Because this consumption is significantly higher than MdL uses, it can be assumed that MdL is locked in at their current billing rate. Finally, it was discovered that ENEE was sponsoring a nation-wide program in Honduras to switch all the incandescent lighting to CFL’s. ENEE offered to donate 50 CFL bulbs to MdL as part of their program, and they also offered to visit the facility towards the end of the week to review practices to further reduce MdL’s electrical consumption. After the billing methodology was obtained, analysis could be performed on the billing data. First, the concern that as the orphanage has gotten larger, the electrical consumption has increased was investigated. Figure 1 shows the historical consumption by kW-h. The data shows a very small upward trend, but no huge increases in consumption over time. A correlation could be run comparing the consumption to the amount of people present at the facility during various times; however, this data has yet to be provided.
kWh
8000 7000 6000 5000 4000 3000 2000 1000 11/24/05
11/24/06
11/24/07
11/24/08
2/24/05
5/24/05
8/24/05
2/24/06
5/24/06
8/24/06
2/24/07
5/24/07
8/24/07
2/24/08
5/24/08
8/24/08
Figure 1: MdL’s historical electrical consumption by kWh
Next, the billing was investigated in an attempt to validate the $0.19/kW-h figure obtained from the meeting with ENEE. Figure 2 (on the next page) is a plot of the price per kW-h over time. First, it is important to note that the billing under no steady period was charged at $0.19/kW-h, and the cost only eclipsed this rate in three instances. All three of these instances appear to be a charge of around two times the amount during that period of time.
3
2/24/09
0
Cost/kWh ($) $0.30 $0.25 $0.20 $0.15 $0.10 $0.05 $0.00 11/24/05 11/24/06 11/24/07 11/24/08 2/24/05 5/24/05 8/24/05 2/24/06 5/24/06 8/24/06 2/24/07 5/24/07 8/24/07 2/24/08 5/24/08 8/24/08 2/24/09
Figure 2: Cost per kWh over time
A second meeting with ENEE took place on March 28, 2009 at MdL. Two representatives came to deliver the CFL lights donated, as well to investigate methods to further reduce energy consumption, as well as provide insight into the remaining billing questions. Appendix F shows the specifications required for all CFL lights issued by ENEE. Lights of 8W, 14W, 18W, and 20W were donated. The following recommendations are being made for installing the CFL lights. 8 Watt Bulbs – Use in rooms that have three lights per room, such as in the guest bedrooms. 14 and 18 Watt Bulbs – Use in areas that have two lights per room, such as the majority of the children’s bedrooms. In areas where more light is needed, use the 18 Watt bulbs. 20 Watt Bulbs – Use in areas that have one light per room, or in areas where a significant amount of brightness is necessary. ENEE also recommended reducing the amount of lights in all rooms possible, to use CFL’s instead of fluorescent lights in the rooms where both are installed, and to install CFL fixtures in the bedrooms where fluorescent lights are currently used. They also recommended lowering the lights in the areas with high ceilings, such as in the dining room. In the kitchen, they recommended moving the freezer out of the sunlight if possible, as well as fixing the damage to the freezer’s insulation near the opening. In the computer lab, they recommended reducing the heat in the lab through reflective paint and insulation materials. It was also recommended that some roofing panels be replaced by translucent roofing panels in order to allow areas to be illuminated by natural sunlight. The billing questions were then discussed with the representatives. Specifically, why the bill never reached $0.19 and why the three periods were overcharged. In regards to the rate, they informed that the rate given to us was actually an average over time, and that the actual rate changed daily. In regards to the three anomalies in the data, they did not have answers but promised to inquire about it. However, they did suggest that the corruption of the national government could potentially be leading to overcharge.
4
Defective TED
Part of the energy audit was supposed to consist of a comprehensive analysis of the energy usage for each circuit breaker box at MdL. The Energy Detective (TED) was purchased by Scott Potter from the Institute for Energy and the Environment, to get information on comprehensive energy usage from each circuit breaker panel. TED was installed in the kitchen’s circuit breaker box. The team was unable to get the TED to work. The team then tested the TED in the circuit breaker box to the computer lab. The team e-mailed the company that made the TED. The e-mails resulted in the diagnosis of a defective unit. The cost for international priority shipment of a new unit was too much for the team to justify covering it. Therefore it was not possible to do a comprehensive analysis of the energy usage for anything that did not plug into a standard wall outlet, such as an entire room or the water pump.
Variable Frequency Drive and Transfer Switch Installation
Recently two generators were donated to MdL. MdL wanted to use one of them to pump water from the water cistern to the rest of the complex during power outages. To accommodate this need, a transfer switch, shown in Figures 3 and 4, was installed to allow the pump’s power supply to be switched from the electric grid power supply to the generator’s power supply. Theoretically the generators were not capable of supplying the pump’s initial power load but could maintain the pump’s steady state operations. This was determined from an analysis of the pump’s and generator’s specifications done by electrician and practicing electrical engineer, Jeff Hutchinson during his visit earlier in the year. A three-phase variable frequency drive (VFD), shown in Figures 3 and 4, was installed to allow the generator to handle the pump’s initial load. Unfortunately the pump was a onephase pump. The VFD could not be altered to be compatible with a one-phase pump. Therefore, the VFD was ineffective and removed.
Figure 3: The final configuration of the main circuit breaker box for the MdL complex (right), and the transfer switch (bottom left) after the VFD (top left) was removed from the system
5
Figure 4: The VFD (top) after it was disconnected from the circuit and the installed transfer switch.
Figure 5: The circuit breaker box for the MdL complex.
6
Energy Audit
In performing the energy audit of the MdL facilities, the Kill-A-Watt became the main method of measurement. The Kill-A-Watt (pictured in Figure 6) is a small device that can be plugged into any 120V AC outlet that records several useful measurements for most appliances and electronic devices including voltage, power factor, frequency, total complex power, active power, and the length of the data collection time period. To measure the power consumption, the appliance to be measured is plugged directly into the Kill-A-Watt, which is then plugged into a standard wall outlet. Next, the billing rate is set on the Kill-A-Watt, and the devices are left for a time period so that the Kill-A-Watt can record the data from the appliance and the outlet. More accurate cost projections result from longer data collecting periods.
Figure 6: Kill-A-Watt EZ
Various appliances’ and electronics’ power consumption were monitored at MdL. A main focus of the energy audit was the possible improvement of the energy consumption of the refrigerators in the kitchen. Scott Potter mentioned that simply moving a refrigerator farther from the wall would allow the coils on the back to cool faster and result in lower energy consumption. To test this method at MdL, the power consumption of the two refrigerators in the kitchen were monitored for a 24-hour period in the locations we initially found them. Then, the refrigerators were moved varying distances from the wall and the resulting drops in energy consumption were recorded over additional 24-hour periods. An important aspect of this part of the energy audit was deciding on a reasonable distance for the refrigerators to be from the wall. It was crucial that the refrigerators were not moved so far from the wall where it would be unreasonable or inconvenient for them to be located. Doorways and light switches were obstacles in this endeavor. The reasons for moving the refrigerators from the wall were also explained to the kitchen staff at MdL. This was done out of concern that the ..."
|
You need to upgrade your Flash Player , or try to enable javascript in order see this document properly.
|
|
Comments
