Upgrading or replacing a boiler system presents one of the most daunting and expensive challenges a large facility can undertake. When the time comes—whether the current system is outdated and inefficient or it fails outright—facility management must understand the process in order to set facility management goals and make the right decisions to fulfill their energy and efficiency needs. More than 1,200 Veterans Administration medical centers and outpatient sites across the country are undertaking system overhauls like this.
Driven primarily by environmental concerns, the VA has undertaken boiler system upgrades in all their facilities. Most of the facilities will need to update their equipment, but some will require a full-system replacement. With more than a thousand facilities in need of evaluation, it’s a huge undertaking—but administrators believe that the long-term savings will make the effort worthwhile.
Why make the change now?
One of the driving factors in getting this change implemented right away is regulatory. California, Texas, and New Jersey have implemented air quality standards that will not be met by older boiler systems. They must be upgraded or replaced.
These old systems often used technology that sacrificed environmental safety in favor of cost savings. Some systems incorporated metal mesh burners, which utilized filters that clog easily. The gradual clogging of air filters leads to less excess air, which leads to higher NOx emissions. NOx emissions are a combination of nitric oxide (NO) and oxygen. Nitric oxide is the result of fuel combustion and alone is not considered hazardous; however, combined with oxygen it is the source of fog, acid rain, and ground level ozone, which has been linked to myriad health issues. And while some other systems might have utilized technology to reduce overall NOx, these systems had increased electricity costs.
A second reason for the VA system upgrade, therefore, is to address these cost concerns. Today’s upgrades do not require air filters, which used to add to operation costs. Upgraded systems also offer quick-change, dual-fuel capabilities, switching between gas and oil firing in less than three minutes. This saves on service costs, since multiple people are no longer needed to make the changeover. The greatest cost reduction, however, is in the demand for electricity. There is a reduction of up to 60 percent in electric consumption.
One way to realize a cost savings is by employing a system that allows one to adjust the output according to the demand. This adjustment is achieved via what is called the unit’s “boiler turndown ratio,” which is the ratio of the maximum heat output to the minimum heat output at which the boiler will operate both efficiently and controllably. As the desired temperature/pressure point is reached, the heat source is turned down, and if the temperature/pressure falls, the heat is turned up. In applications like the VA centers, which require boilers to operate at a low proportion of their maximum output, a high turndown ratio is desired, and that can be achieved with modern upgrades. Traditional burners using fiber metal mesh provide a 3:1 turndown; however, with recent advancements in the field, there are now systems that can provide a 9:1 turndown or higher depending on NOx requirement. These systems can achieve ultra-low NOx emissions without the use of FGR (flue gas recirculation).
In addition to the cost savings realized through a 9:1 turndown, there is also the reduction in required maintenance. Not only are multiple people no longer needed for a dual-fuel changeover, but operating and monitoring the systems are also simplified. Older systems require constant maintenance to ensure fuel efficiency and emission control. For example, many older systems include jackshaft linkage. Due to the complexity of these systems, they require constant fine-tuning and maintenance by highly skilled operators. Maintenance of an upgraded or new system is far less complex.
Newer monitoring equipment also means fewer people are needed for hands-on examination of the system. Typically, with an older system, there was a boiler in each building—and that meant someone needed to be on location to monitor those systems. The ability to house the entire system in one location, or to upgrade the system to monitor from one location, results in lower maintenance costs.
Upgrade or replace? A case study
Determining whether to upgrade or replace a system depends on two things: the age of the existing boiler(s) and the application for the new system. Generally, systems that have been in service for 25 to 30 years would require replacement instead of an upgrade. This was the case for the V.A. Erie Medical Center in Erie, Pennsylvania. Their system had been in place for three decades and required complete replacement. In order to make the most impact with this important project, they built an entirely new boiler plant from the ground up.
The engineering team at the VA determined that existing system had met its lifespan, and they wanted to replace with latest technology. Any short-term replacement would have simply been a Band-Aid. They realized, however, that a project of this magnitude would take time to do properly. The engineering team at the VA chose Greenland Enterprises, Inc. to handle the entire project based on their central plant expertise and track-record at other healthcare facilities.
Based on the campus steam load, they determined that the replacement equipment would consist of two 400-horsepower boilers and one 200-horsepower boiler. Installation of the new boiler system took four months. From the ground up (including the new construction), the work on the project took 14 months to complete.
This new plant will provide at least a 60 percent reduction in electricity consumption, which will be accomplished using a variable frequency drive. This technology can run with fan speed at a lower rate. For example, changing the power from 60hz to 30hz speed can cut the horsepower by eight times. Therefore, a 400-horsepower system would be cut to 60-horsepower. According to Steve Seckler, Vice President of Operations at Greenland Enterprises, “Most systems can go from 60hz to 40hz easily. We chose a system that can efficiently go all the way from 60hz to 15hz for additional savings.”
Fuel reduction provides cost savings over the life of the new system. Newer boiler systems can offer a savings of two to five percent. This means that one 400-horsepower boiler with a fuel cost of $500,000 annually can save between $10,000 and $25,000 a year. This new Erie plant, with its two 400-horsepower boilers and one 200-horsepower boiler, will save the hospital between $25,000 and $62,500 in fuel costs annually.
Is it time for an upgrade at your facility?
A boiler upgrade project like the one undertaken at the VA Erie Medical Center is clearly something that takes significant time and money to complete. But in the end, management determined that the expense and effort will pay off in the long run. Could it be time for you to look at a similar project for your facility? Here are some points to consider when making your decision.
Sustainability
In large facilities, sustainability can be neglected when considering boiler systems. Facilities like hospitals often rely on older boilers and choose the “Band-Aid” approach of patching and maintaining them out of necessity. This method is not sustainable. Upgrading to a new boiler is the best option for long-term, sustainable improvement.
Sustainability also refers to the environmental impact of a system. With ever-changing state requirements, it is important to choose a system with enough flexibility to face these new demands as well as future ones.
Fuel-efficiency
To sufficiently meet the heating and energy load demands of healthcare facilities, old boilers burn an inordinate amount of fuel. New boilers bring added efficiency and substantial fuel savings. There is also much being done in the realm of alternative fuels for boiler systems. Bio-fuels and liquid wood are two segments of the alternative fuel market that are making great strides.
Operations and Maintenance
New boilers are streamlined to operate more smoothly and efficiently than old boilers, which can be challenging to operate and maintain. The older boilers often take much longer to heat up, and they are often kept running to meet heating needs. New boilers are designed to heat up quickly and can be adjusted to handle variable loads to ensure less energy consumption.
When considering an upgrade or replacement, no matter what the reason may be, all factors of the operation need to be addressed in preparation for a system shut-down. A project of this magnitude, from the initial bid process to completion, will require a minimum of several months (for an upgrade) up to a year or more (for a complete boiler replacement). The impact of this change, and thus the importance of the decisions made during the process, are why so many V.A. hospitals and medical centers are carefully reviewing their future energy options.
About the author: Dan Wallace is Vice President of Research & Development at Preferred Utilities Manufacturing Corporation, an engineering-based manufacturer of products for commercial, institutional, industrial and nuclear power facilities.