Energy

Metering Enhances Efficiency

Identifying tools to prevent energy loss

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Credit: Continental Control Systems
Continental Control Systems designed and manufactured the WattNode energy meter, which has a wide range of uses. Manufacturers and small businesses alike use WattNode energy meters to track their energy use.
Researchers at Washington State University had discovered occupants in high-efficiency buildings were so frustrated with unresponsive motion sensors and temperature controls, they had found unconventional solutions to thwart the energy efficiency tools, Smithsonian Magazine reported in late November 2017.

Examples included a weather observatory in which the building’s lights had no switches, only motion sensors. In order to view the night sky, scientists had to stay absolutely still for 15 to 20 minutes to get the sensors to turn the lights off.

Occupants of an office building complained that the lights would turn off too easily because the motion sensor was aimed at a corner. So they set up a toy bird that dips its bill into a glass of water and rises again and again to keep the lights on all the time.

In another office, occupants were uncomfortable with the temperature set by a smart thermostat. So they held cold popsicles to the sensors to increase the temperature. Alternately, they taped a coin to a windowsill to reflect light at the thermostat, forcing the air conditioning to come on.

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The conclusion the researchers reached was that poorly considered architecture and design cannot just rely on data; they must consider the experiential aspects of buildings. The coauthors of the study hope their work can make designers more sensitive to building occupants’ needs and realities to avoid the many tweaks making efficiency tools ineffective.

The study’s results were published in the September 2017 issue of Energy Research and Social Science, an Elsevier publication.

The two case studies profiled below illustrate the importance of integrating occupants into the process of making buildings energy efficient and they offer two very different approaches to finding and preventing energy loss. Along the way they prove that metering energy use is one of the most important tools to support those efforts.

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The ENERGY STAR Tool Book
CalPortland, the well-known cement provider, has won the US Environmental Protection Agency’s ENERGY STAR Partner of the Year Award for the past 13 years. It is also an ENERGY STAR Industrial Challenge winner. William Jerald, chief energy engineer for CalPortland, says, “We have a core culture in energy efficiency. We enjoy the positive view since we’re a mining operation.”

CalPortland has built its energy efficiency program around the ENERGY STAR program. Another advantage of the program is networking. “The program helps us network and we meet with Toyota and other major companies participating in the program. We teach each other and constantly help each other out,” says Jerald.

Founded in 1891, Cal Portland is headquartered in Glendora, CA. It produces and distributes cement, concrete, asphalt, and aggregate on the west coast of North America, serving six US states and two Canadian provinces. The company has three cement plants, two in California in Mojave and Arroyo Grande and one, the largest, in Arizona near Tucson. Each generates 25- to 30-MW loads. There are also 150 smaller plants and operations scattered along the West Coast.

Jerald started by installing energy monitoring devices at the cement plants since he needed data to understand the amount of electricity the equipment was using. He says monitoring is really important when you have multiple production units on one meter. CalPortland has 19 plants in the ENERGY STAR Challenge and all have the monitoring devices to collect the data. The smallest operating plants were excluded.

Jerald had Continental Controls WattNodes installed as submeters. “A simple e10 controller collects the data from the WattNode and stores it in servers. This data is then shared with managers. The goal is to improve efficiency by 10%,” he says.

Jerald described the ENERGY STAR process for reducing energy use at each of CalPortland’s plants as a treasure hunt—avoiding the word “audit.” He and CalPortland helped EPA create its “Energy Treasure Hunt Guide.” (See the sidebar for a summary of the Guide.)

Each plant will have its own personality, Jerald says. For example, some plants have compressed air, which is a huge energy user. “Some people don’t know that,” he says.

Before he leads plant personnel on a treasure hunt, Jerald asks them to gather relevant data on energy consumption and costs, plant equipment, and processes and production. He identifies the 10 top energy users in the plant. Once on the tour, they identify specific problems. Are the compressors not configured properly? Are fans running on the dust collectors? Where can variable speed drives be installed on fans to reduce running time?

At the end of the day, Jerald and the plant personnel hold close-out sessions where the three top energy users are identified and a plan is created to implement projects and monitor them along the way. The corporate engineering group is also brought in to assist the plant with project implementation.

Jerald says the company has capital budgets for each project which identifies costs and savings. The goal is a three-year return on investment for each project. But Jerald says since they’ve won the ENERGY STAR Partner of the Year award 13 years running, “We can have leniency on the three-year ROI rule.”

Proving the Efficacy of Meters
Continental Control Systems, headquartered in Longmont, CO, designs and manufactures the WattNode energy meters and Accu-CT current transformers. John Browne, applications engineer at the company, has a rich background in energy efficiency research. He was one of the first users of the WattNode energy meter when he worked at the Architectural Energy Corporation.

Browne says some of the company’s major market areas for its WattNode are in tenant metering in the commercial real estate business and in sales to original equipment manufacturers (OEM) where, for example, companies are installing meters on solar systems to measure the amount of solar energy produced. Continental Control Systems got its start by supplying meters to government research labs and energy efficiency consultants which needed to collect energy data in homes and businesses. Surprisingly, the researchers had no meters small enough to fit in a residential electrical panel, says Browne. Now, WattNode meters are being used in commercial buildings to manage energy, and they play a crucial role in implementing utility demand response plans, says Browne.

Browne explains that measuring power is complicated. It took years to develop the software code that goes into the metering chip to allow it to calculate energy usage.

Meters have a wide range of uses. For example, Browne knows of a welding shop owner who watches his meter while welding to avoid going over his electrical demand target. A school district in Colorado installed a meter to manually control electricity use to avoid charges. Browne has also seen people using meters to measure CO2—so many kilowatt-hours (kWh) equals so much CO2.

In another segment of the market, Browne says, “We work with can manufacturers who find it valuable to track energy used in manufacturing their products.” Tracking energy used also helps in maintaining equipment, he says.

Server farms are finding a use for meters. In hosting services, the energy used to provide air conditioning to servers can be charged to the client. “We developed an 84-circuit meter for ISP providers that allows them to bill customers for the amount of electricity used by each server,” says Browne.

The California Energy Commission has estimated there are four million roofs with rooftop air conditioning units, Browne says. Dampers can be broken in the open position, and bring in 95°F air in the summer heat. Metering can be used to identify these breaks by tracking electricity use. The CEC estimates half the AC units that are broken on any given day could be repaired at $50 each.

Credit: St. Vrain School District
The Center for ReSource Conservation in Boulder, CO, has implemented an energy education and conservation competition in several school districts in Colorado. Students at Sunset Middle School in the St. Vrain School District are studying energy usage in their school building with the help of their teacher, Walid Hamzi.

Continuous Energy Monitoring Sustains Savings
eGauge, headquartered in Boulder, CO, manufactures meters, creates software, and sells both worldwide. Ed Pantzar, marketing manager, says renewable energy is the biggest source of eGauge’s sales, including solar systems. “It’s important to track solar usage with meters” since the meters have the capability to alert operators when electricity production is low. Inverter failure is the most common reason for a group of panels to fail, he says.

Other popular applications include measuring tenants’ electricity usage in leased office space and for demand management, Pantzar says, where users want to know the amount of power used on equipment. Utilities charge a lot for high peak demand when electricity use is creating stress on the grid. A meter can detect peaks, for example, when three pumps turn on at the same time, driving up costs. This situation can be avoided when the pumps can be turned on in sequence by the building’s energy management system, Pantzar says. He also explains that data from the meter can be put into the management system.

eGauge participated in the “ReNew Our Schools” program at St. Vrain Valley School District. It installed meters in 14 schools in the district for a one-month competition where students and staff reduced energy use. The data from each of the schools was compared to the three-month period before the competition started to serve as a baseline. Some schools saw reductions up to 18%, and overall achieved 8% normalized savings.

However, facility energy managers found significantly more information in the meters, Pantzar says. By reducing wasteful equipment and operations such as air conditioning units that cycled on for one hour during winter months, the school district projected they would save between $50,000 to $200,000 on their electricity bills.

Using Education to Reduce Energy Loss
Resource Central in Boulder, CO, under its ReNew Our Schools program, began an energy education and conservation competition at 14 Colorado elementary, middle, and high schools in
the St. Vrain Valley School District in the spring of 2013. The success of that competition led the ReNew Our Schools program to expand to other schools in St. Vrain School District and eventually to other school districts throughout the state.

The success of the program began crucially with eGauge installing its meters in combination with Magnelab current transformers in the 14 schools. The eGauge device doubles as an energy meter, data logger, and web server in one handheld energy monitoring meter.

Kathy Crosdale, manager of ReNew Our Schools, says the competition was between the 14 schools to see which one could reduce the most energy use. The three winners were each awarded $25,000. Both behavioral and technical changes were included. Crosdale says all of the schools continued to maintain their reduced energy use after the competition concluded.

The goal was to engage students, parents, teachers, administrators, and maintenance staff in finding new and innovative ways to reduce electricity consumption, increase energy literacy among all groups, and grow community awareness of their energy footprint. Students and teachers did it by monitoring the school’s energy consumption on the eGauge meter in real time while turning on and off equipment such as lighting.

The 14 St. Vrain schools collectively reduced electricity consumption 4.9% to 7.8% during the month of the competition relative to baseline usage for the three months prior. The top schools reduced energy consumption 17% to 18%. This reduction saved the school district $7,800 on energy bills. Interestingly, surveys of 1,600 households of the students indicated they were able to stay engaged through online viewing of the real-time energy consumption tracking device from eGauge.

With the work of Dara Ward, St. Vrain’s energy and sustainability manager, the school district has created a year-round energy program called Resource-Wise. It includes in-depth training, resources, and incentives as well as educational materials to meet Colorado state curriculum standards. St. Vrain hosted additional ReNew Our Schools competitions in 2014 and 2015.

Crosdale says when she was recruiting school districts in Colorado, the older energy managers wanted nothing to do with the project because they were convinced behavioral education would not work. However, new young energy managers like Dara Ward picked up on the idea. And the schools that have adopted the program have the numbers to prove they are reducing energy use. Now there is a waiting list among the approximately 60 school districts in Colorado to join the program, Crosdale says.

Funding is provided by the Colorado Energy Office and an east coast family foundation which took notice when it saw students participating in the program at a science competition. eGauge donates 20 devices each year to install in competing schools. Furthermore, some school districts purchase additional eGauge meters after the competition ends to install in their remaining schools. Jefferson County Schools was one such school district. It purchased meters for its remaining 160 schools, and St. Vrain now has 48 eGauge meters installed.

Credit: St. Vrain School District
A sixth grader is explaining the school’s energy usage to his classmates as part of the energy education and conservation competition partly funded by eGauge. The company installed its meters and donated software to 14 schools.

Competition Improves Behavioral Learning
Dara Ward concluded in a research paper that behavioral training can have a lasting impact on electricity reduction in the schools compared to those schools which did not participate in her Resource-Wise program.

The competition required that the schools who sign up come up with efficiency recommendations for school facilities, projects, or programs. Participating schools received toolkits, training, resources, materials, and district support. In addition, Ward developed a mentor program to match local energy professionals with schools to provide guidance and recommendations. These professionals included energy industry experts, sustainability consultants, and utility representatives who all volunteered their time to assist students. The mentors and district staff used the real-time data produced by eGauge meters to support claims and nuances in building energy consumption and teach lessons around reducing electric loads.

Students viewed the real-time data to observe whether their actions were reducing electricity consumption. Resource Central and Cube Resources produced user-friendly dashboards so the schools could view their progress. The online displays extracted eGauge data to develop predictive weather-normalized baselines for each school during the competition.

The ability to observe the impact of their actions encouraged the students and staff to conduct energy investigations. With the help of custodial and/or district staff, students spent time after school hours testing the impact of turning off lights or manipulating HVAC schedules. They walked around the school viewing energy consumption on portable internet devices to observe shifts occurring—for example, when turning off gymnasium lights.

Credit: Continental Control Systems
Cal Portland’s Oro Grande plant is one of 19 cement plants where WattNodes were installed
as submeters. Data is collected and stored in servers for use by managers. The goal is to
improve efficiency by 10%.

Students began to understand that adopting small changes such as minimizing lighting and plug loads and reducing energy hogs could lead to bigger results. A few schools adopted “blackout lessons” where each classroom projected the eGauge meter data and turned off all the lights at the same time so the students could see the large electricity reduction happening live. Both students and teachers found the exercise fascinating in that it showed them how they could impact their environment. It motivated them to take advantage of daylight rather than overhead fixtures, unplug equipment, remove personal appliances, and pay attention to HVAC schedules.

Students at several schools identified school start times, peaks, and end-of-school shutdown times, allowing them to evaluate patterns and anomalies in building consumption, which led them to questions about schedules and inefficiencies. Students requested later start times, earlier shutdowns, or even reduced air conditioning or heating set points to increase savings. They discovered that slight adjustments were not felt by building occupants and had no effect on the school learning environment.

Empower Staff through Training
Ward says the St. Vrain Valley School District has not identified overall savings for the district in the years following the first competition in 2013 when the district saved $7,800 over 28 days. So the district does not know if the original projections by eGauge will be met. But two competitions at other schools in 2014 and 2015 saved $3,230 and $4,290 respectively over 19 days.

Ward says she prefers to talk of savings in terms of square footage. In the 2016–2017 school year, participating middle schools in the Resource-Wise program reduced electricity consumption from a 2013–2014 baseline of 67 kBTU per square foot to 59 kBTU per square foot, or 7%. Non-participating middle schools reduced electricity use by 3%. Elementary schools reduced their energy consumption from 72 kBTU per square foot to 60 kBTU per square foot, or 11% compared to nonparticipating elementary schools, which reduced electricity use just 3%.

About half of the 60 schools in the district are very engaged and 48 have eGauge meters. The numbers prove that the schools that participate in the year-round Resource-Wise program do substantially better, Ward says. “Using eGauge, we can improve how the buildings operate,” she says. “These actions are extremely important.”

District and building engineers were also drawn into the program. They identified maintenance and modifications that have since been incorporated into the maintenance of the participating schools. Ward says these included building tune-ups, coil cleaning, cold weather procedures, and custodian training.

Building tune-ups involve external engineering consultants doing walkthroughs and checking building controls to find sensors not working properly, dampers stuck open,  or boilers that have set points that are too high.

“We’ve been lucky to have utility funding from Longmont Power & Communications, Xcel Energy, and United Power. They have contracts with engineering consultants who do building tune-ups,” she said.

Dirty coils on fans can impact indoor air and affect operating efficiency, Ward says. They brought in an outside company to clean the coils using pressurized water. The impact of the cleaning could be measured before and after the cleaning on eGauge meters. The payback was six months, and the fans are running more efficiently she says.

Cold weather procedures were updated. The district experiences $50,000 to $100,000 per week on costs to heat the school buildings when temperatures fall under 10°F about two weeks per year. Before eGauge meters were installed, “We didn’t know what the costs were,” says Ward. “We can now pinpoint start and stop times on motors and fans and are investigating several tactics,” she added.

These tactics include having the HVAC staff monitor weather and online temperatures more closely, keeping in mind that water pipes are vulnerable when outside temperatures fall to the 10 level.

Custodian training has been especially rewarding, says Ward. She leads the sessions, going through conservation lists about what to look for: cold spots, lab safety, and how to submit work orders. She says she is trying to empower the custodians to report problems early, as soon as they are identified, to get in front of them.

The training has energized the custodians and it has opened the door for them to have an impact on their schools. It is an extra added value for the districts, Ward says. “Some of the best ideas come from them,” she adds.

The district does have issues with the 30 to 40 portable school rooms they have, which are energy intensive, using almost 20% of the school district’s total energy use, Ward says. They are small square buildings with very little insulation that rely on electricity for heating. Installed eGauge meters are giving the staff an idea of their energy intensity, she says.

St. Vrain is also developing renewable resources. It has two small solar systems on rooftops—6 kilowatts (kW) and 20 kW—and a 2.4-kW wind turbine. It is planning to install three solar projects totaling 1.2 MW on three buildings in early spring 2018 to replace 79% of their electricity usage, Ward says.  BE_bug_web

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