Energy management unlocks energy savings and boosts energy production.
By Ed Ritchie
There’s no need to belabor the point that distributed energy offers substantial gains to energy efficiency. But for distributed energy installations, that genset and heat capture hardware is just the beginning of the story, as well as the beginning of a site’s efficiency gains. The ideal onsite power project wrings even higher efficiency from control and monitoring equipment that can improve fuel savings, and optimize demand response performance.
The US Army is taking advantage of some sophisticated control systems at a number of forts that have installed microgrids. The latest project is at Fort Sill Army Base, OK, and it’s the fifth Army site to configure their onsite generators with control systems from PI Encorp, Fort Collins, CO. The Encorp system includes collaborative concepts from Sandia National Laboratory and the Army Corps of Engineers, all designed to link together an existing installation of four separate gensets into a flexible unit. Using the company’s Automatic Paralleling Switch, the system can peak shave or export power to the base utility. Also, the Fort’s operators have the option of interconnecting a single genset with the base utility grid, or all four at once. When grid connected, the microgrid can dispatch 1 MW at the facility, but if the utility’s grid fails, the generators can operate independently.
“A microgrid is basically connecting different generation assets together with some storage and using multiple loads and multiple buildings,” explains Michael Clark, president, PI Encorp.
With our hardware located inside each device—as well as the point of common coupling for the grid—systems like the one provided by Encorp are stable says Clark, in part because of the ability to control assets to provide electrical and thermal energy to critical loads. Integrated load shedding sequences also allow for dynamic control in the event the grid goes offline. As Clark explains, during those times when the grid becomes unavailable, the control system can “dynamically control the load at that facility to drop off to match the generation capacity in the microgrid. So they have total control on the generation side of the load for optimal operation and stability.”
Shedding Load Builds Profits
Capturing the financial benefits of load shedding to satisfy utility demand response programs is another area requiring stability. Encorp recently announced the launch of its Demand Response (DR) System Controller, which features both supply and demand-side capabilities.
In January, a Class A office building on Madison Avenue in New York City, NY ordered a DR System Controller to help ensure that the customer meets the demand response requirements of the local utility, Con Edison. The system-level controller will aggregate two large power loads at the office building, controlling 1.5 MW.
“This building has the only grid interconnected system in New York City with a synchronous generator on Fifth Avenue,” notes Clark. “There are a lot of cogeneration systems in New York, but they don’t allow interconnection with the grid.”
By including demand response that can work with multiple loads, the building has more flexibility. “For example, “ says Clark, “when the demand response signal is initiated from the utility we just don’t turn off selected loads. We will turn off multiple loads depending upon the degree of reduction required.
Net Zero Gaining Steam
At Monroe Community College, a design-build project with Siemens, Inc. for a 4,160-V, 5,400-kW cogeneration plant serves the campus electric load in parallel with Rochester Gas & Electric. Nearby, a cogen plant serves the Monroe County Iola Complex, including Monroe Community Hospital, Pure Waters Operations Center, and the Health and Social Services Building. The project included the installation of seven 1,350-kW, natural gas-fired generators and six 350-hp, dual-fuel steam boilers. Heat from the electrical generating process is converted to steam and domestic hot water for the Iola complex. Again, these systems provide heating and electricity in parallel with the local utility.
The concept of net-zero buildings continues to drive energy efficiency, illustrated by the Army’s recently articulated goal of developing 25 “net-zero installations” by 2030. Currently the Army has a pilot program to develop a total of 15 installations, composed of five each in the categories of water, waste, and energy. Additionally, one installation will be net zero in all three categories. The US Department of Energy lists only eight zero-energy buildings in the US on its high performance-building database. But on the other side of the Atlantic, the United Kingdom is targeting zero carbon construction for all residential buildings starting in 2016, while their new residential construction must meet levels of energy efficiency at least 45–60% lower than the equivalent built in 2006.
Meanwhile in the US, as the new school year opened, students and junior faculty began moving into net-zero housing units at University of California, Davis. The six buildings include 42,500 square feet of ground-floor retail and have established the first phase of West Village, the largest net-zero energy development in the US.
“A lot of college campuses are interested in net zero, but there is also a growing trend of trying to achieve net-zero building structures in commercial real estate and private companies,” says Paul Golden, national business development manager, Energy Solutions, Schneider Electric, Palatine, IL. “But many building owners want fast returns on their investments.”
And then again, misconceptions about technology may exist with management, such as in the hotel industry. (See Additional Content: “Hotels Say “No Vacancy” to Energy Management”.) Nonetheless, the results of energy management systems are impressive, and according to Golden, there are some major trends driving rapid growth in the industry.
“The interesting thing is that more and more green leases are being written now, and we see the large tenants and brand tenants that take multiple floors on 15-year leases in a building requiring LEED [Leadership in Energy and Environmental Design] certified buildings. A number of years ago you could make the argument that you could charge more per square foot on a LEED-certified building, and now it’s a question of whether you can attract a tenant at all.”
Smart Meters Push Intelligence
Many of these companies are required to provide reporting on carbon disclosures or the data for the Dow Jones Index. In such instances, energy becomes critical, and accurate measurements are required in order to report energy efficiency and sustainability efforts. To make buildings green, they have to be smart, and Golden notes that it requires participation from all the stakeholders, such as the owners, tenants, building operations, and maintenance. The first step is monitoring energy usage, and smart meters help, but they’re just the beginning.
Microgrids connect different onsite power assets.
|Photo: American Auto-Matrix
Using different generation assets together —along with energy storage—gets at the heart of energy management systems.
“There’s a lot of intelligence in metering, but they don’t have any direct interactive control with anything,” he says. “If there are meters in a building, it’s more than likely a sensor device in multiple locations in a building or across an enterprise, feeding data to a single-building control system, or something that’s interactive with the eye number of systems. But what’s managing your ice storage system is not the same as what’s running your chiller plant. And your lighting control and occupancy will be different.”
As an example, Golden cites the Bank of America headquarters building in New York. “It’s one of the greenest buildings on the planet at this point,” he notes.
The building, also known as One Bryant Park in midtown Manhattan, is the world’s first office tower to achieve the LEED Platinum rating, the highest level of certification awarded by the US GBC. “We have a base building electric metering system, and we’re doing everything from taking the existing meter readings and info from multiple systems and data from the building automation system and the operation of the cogeneration and ice making unit. We have the ability to interact and integrate those systems and provide visualization tools for building operations.”
One Bryant uses Schneider’s ION Enterprise software server and the system monitors tenant submeters and communication gateways to collect energy data from the building automation system, plus the operations of its sophisticated cogeneration plant and ice-making equipment. One Bryant receives day-ahead, hourly pricing for electricity, and the expanded metering system allows Durst to manage this rate change by tracking building and tenant energy use in real-time, managing energy use during peak hours to control costs, and leveraging energy information for more intelligent building operations.
Building Automation Reduces Carbon Emissions
Data management plays a key role at the new residence hall at Cheyney University, Cheyney, PA, doesn’t achieve net-zero performance, but it does demonstrate some significant energy savings gained by the use of building automation. Cheyney embarked on its building automation program in 1994 by contracting with American Auto-Matrix, Export, PA, a manufacturer of microprocessor-based, applied, networkable controllers for building automation and other markets.
“We chose Auto-Matrix products then, and in 2010 we started a major energy overhaul. Because of their ability to interface with their legacy products, we stayed with them for the expansion,” recalls Carl Williams, deputy director, Cheney University. “We had control panels installed in the new 400-bed residence hall, and since November of 2010 we have saved about $127,000 with this installation and lowered our BTU index from 150,000 BTUs, down to approximately 80,000 BTUs per square foot. Being a state institution, we are tracked by the Department of Environmental Protection for our annual emissions, and we have lowered our CO2 emissions by 82 tons.”
Cheyney relies on a new area control solution called AspectFT Enterprise, a Web-enabled area control solution that uses a Web server, according to Rocky Moore, director of business development, American Auto-Matrix. “AspectFT Enterprise is designed for large multi-site, multi-building situations where you’re going to pull in a lot of data and a lot of information from multiple buildings on the same campus or in a global setting,” says Moore.
The system allows Cheney to aggregate their data together and put it into a MySQL database. “That’s an industry standard, and it allows them to utilize programs of their choice,” notes Moore. “Should they choose down the road to slice and dice it in some way that’s not on the webpage, they could go in with something like Crystal Reports or link it to something like Microsoft Excel, and pull that data and look at it any way they want to.”
Aspect can also use one of over 45 programs that utilize the iCalendar protocol as a scheduling tool, including: Outlook 2007, Google Calendar, or Apple’s iCal to change schedules in a building. “So their entire facility is scheduled via the Web, and they don’t need to know a special scheduling tool,” adds Moore.
For enhanced reliability, the AspectFT system follows a philosophy of distributed intelligence. “That means it has schedules running at the enterprise level, but those controllers also have schedules built into them,” he says. “So those controllers in the buildings have the capability of running on their own internal schedules when the brain of the building goes down because its Internet connectivity was lost or the network and the server crashed.”
In addition, the facility has smaller level devices called AspectFT matrix devices that are lower level devices acting as the brains for each individual building. It’s another point of redundancy that can perform and control functions and routines.
Avoiding a Demand Response Meltdown
The AspectFT system makes scheduling easy for building automation, but what happens when you’re in a manufacturing environment and trying to schedule multiple megawatt loads in a demand response scheme? It can be something of a challenge, according to Chris Buck, plant manager of DONSCO Inc., a foundry in Wrightsville, PA.
“We are a medium- to high-volume foundry casting on average about 150 tons a day of molten iron,” says Buck. Up until 2010, DONSCO ran their furnaces and other heavy loads at night to take advantage of off-peak electricity pricing, but deregulation brought new pricing and distribution penalties.
“The difference between on-peak and off-peak was a factor of almost eight, so we were basically at a two-megawatt low during the day, and over 60 at night,” recalls Buck. “With the change in deregulation and distribution calculations we saw a 700% price increase in just our distribution portion of the bill. We knew we were going to be going with real-time pricing and had a generation strategy, but with the distribution portion of it our hands were tied. We needed to hedge that 700% price increase.”
It came down to two options: first was a choice of participating in the utility’s Interruptible Load for Reliability program, where DONSCO would be paid for every megawatt they could shed. But the plant was already running lean. The second option was a Synchronous Reserves program, with events that occur continuously throughout the day and requirements to shed load within 10 minutes of notification.
“Obviously, the challenge with that type of program is that 10 minutes is not a lot of time,” notes Buck, “and that’s what led us to working with Powerit Solutions because they have a product that was able to react that quickly.”
Based in Seattle, WA, Powerit Solutions offers their Spara energy management system, an integrated hardware/software product that acts automatically to increase energy efficiency, cut peak-rate usage, and respond to utility demand response and real-time pricing signals.
Many industrial companies in the US and worldwide are paying more than they need to for electricity because they aren’t taking advantage of utility programs, according to Patty Solberg, director of product marketing at Powerit. “Automation really is the only solution,” says Solberg. “In a real-time pricing rate schedule a facility can see a different price per kilowatt-hour for a span as short as five minutes, so you can imagine that it’s very difficult to manage from a price predictability and cost predictability standpoint.”
The economics can be persuasive. In DONSCO’s case, the demand control savings amount to $64,200 annually. Additionally, the savings through the PJM’s interruptible program equal $30,000 per year, and then there’s the earnings of $66,000 per year from the Synchronous Reserves program. All told, it took just five months for DONSCO to realize a return on investment from Powerit. But the savings went beyond the annual earnings from the utility.
“There have been added benefits because the software collects data and we can analyze it,” explains Buck. “One of the things we’ve been able to do is use this as a training tool in energy efficiency. For instance, we have a utility crew come in on the weekend and they use compressed air, and I could see that they turned on our 300-horsepower air compressor. But we have smaller compressors, and we were able to go back and show them the impact of the 300- horsepower versus the 150- horsepower machine.”
Buck also found the data useful for training in the plants melting area. Some of the operators were ramping up the plant’s furnaces and risking damage to equipment. With the data from Spara the timestamps of the operators were presented, so they could see why they couldn’t just start a furnace and go have a cup of coffee.
“We could show them the profile of each of the furnaces,” says Buck, “and they got a sense of how the operations impact energy consumption and its direct proportion with the temperature of the furnaces.”
From a costing and job-estimating standpoint, Buck has found it easy to determine exactly how many kilowatt-hours are used in the process of metal melting. He’s able to allocate the melting costs of the operation because Spara is measuring the kilowatt-hours used by each of the furnaces. Monitoring kilowatt-hours also helps in tracking maintenance trends. For example, when a furnace’s energy usage rises above normal, Buck knows there’s either a maintenance issue or a problem with the equipment.
Such benefits are common in a wide variety of energy management and control products. As the technology continues to advance, and high-profile users such as the US Army boost the industry’s visibility, the market will grow substantially.
Writer Ed Ritchie specializes in energy, transportation, and communication technologies.