How Microgrids Can Transform Hospital Energy Usage

Lance Haines, chief technology officer-microgrids, Schneider Electric

Technology and patient care go together. Since the global pandemic, hospitals have aggressively sought digital transformation of their infrastructure as medical professionals seek ways to aid their patients through offerings such as cloud-based smartphone apps that improve patient experience and remote and computer-assisted diagnosis and treatment. Now, healthcare digital transformation is an invaluable service for some patients in public health.

According to The Economist, after all the upgrades — such as Internet of Things (IoT) medical devices and virtual healthcare — are added up worldwide, digital medicine will become a trillion-dollar industry. Healthcare digital transformation will improve patient care, but technology depends on electricity — power at the plug must be 100% reliable, 100% of the time.

Electrical failures in medical facilities endanger lives, which is why power backup systems are both mandated by governmental regulations and incentivized by both carrots and sticks. Electrical distribution systems for hospitals usually consist of two parts — the nonessential electrical system and the essential electrical system. The essential system is where lives could be lost should the power ever go out. There are code-required minimum power requirements to keep that essential system up and running, usually with diesel generators.

Diesel has been a reliable anchor resource for hospitals. If properly maintained, you can count on it during an outage — battery backup is still only cost effective to last for hours, and solar still depends on sunshine. However, diesel fuel is carbon intensive. As energy demands increase, there is an opportunity for hospitals to expand their power portfolio by reducing their dependence upon diesel for their nonessential power backup systems.

Diesel generators also require the need to truck in a continuous fuel supply, which can be difficult — if not impossible — in extreme weather conditions. We experienced the challenges from generator failures at hospitals firsthand during Hurricanes Katrina, Irene and Sandy, which resulted in large evacuations of patients.

One of the many benefits of microgrids is that they can be fueled by multiple energy resources, including natural gas, solar, batteries, and, in some areas, fuel cells. An option like natural gas is reliable and cleaner than diesel. When it comes to resiliency, there isn’t a 1:1 correlation between power failures and loss of natural gas. Natural gas has an excellent record for reliability during extreme weather conditions. On-site natural gas “bullet” tanks can also be added for increased resiliency. For some hospitals, solar power can also be an excellent choice because those facilities typically have a large amount of available roof space — perfect for installing solar panels.

Microgrids offer flexibility through system optimization: They can dynamically optimize which loads are connected to the microgrid to achieve cleaner power and preserve diesel runtime.

As more technology finds a footing in our healthcare system, electrical demands will increase, putting further pressure on the nonessential power system. Utility energy prices will also undoubtedly rise in the coming years — so cost-effective, on-site power sources for nonessential backup power will be critical.

Along with the need for digital transformation, healthcare facilities require an energy transformation to modernize their electrical infrastructure with a microgrid.

The addition of a microgrid to the existing diesel

Administrators often choose to go well beyond the minimum power they are mandated to provide for essential power systems to at least partially cover the nonessential systems, such as newer technologies that improve the patient experience.

Backup power above the code-required minimum level can be met by leveraging power sources that include diesel and modern microgrid technology. The backup system can use the existing diesel to guarantee power for the essential system, for the life and safety of patients and employees at the hospital. A natural gas-powered microgrid can be designed for the noncode required loads that the hospital management demands for patient care.

Microgrids can be provided to healthcare facilities through the energy-as-a-service model. Photo credit: NicoElNino/Shutterstock.com

Microgrids offer flexibility through system optimization: They can dynamically optimize which loads are connected to the microgrid to achieve cleaner power and preserve diesel runtime. There are scenarios where normal loads aren’t at a maximum — the hours of the day when they’re operating at 75%, which leaves headroom in the natural gas generator. Or, if the sun is shining, there can be quite a bit of power coming from the rooftop, or perhaps the batteries aren’t empty yet. Depending on what’s available from these resources, the system can optimize the microgrid portion of the power equation by taking some loads away from the diesel generators and back over to the “greener” side. The power used by these loads will then have a lower carbon footprint.

Furthermore, during an outage scenario, by taking this load off the diesel generators, administrators can potentially stretch diesel fuel longer when reserves can be delayed due to road conditions that can inhibit diesel fuel deliveries via trucks. Diesel Start/Stop Optimization can sense when the electrical load has come down enough. It will shut down one or more of the diesels so long as the remaining diesels can handle the load connected to them.

Additionally, most microgrids in North America are connected to the central utility grid, which means the hospital can receive electricity from the microgrid assets and/or from the utility. Dynamically optimizing this mix can provide significant financial advantages. For example, when the central grid is under strain during the summer months (and the rates are higher), the microgrid assets can provide more of the needed power. If regulations and the contract agreement allow it, the hospital can also sell the microgrid’s idle capacity to the local utility or wholesale market.

In short, microgrids can manage a portfolio of distributed energy assets while increasing resilience. Microgrids can be customized to produce both electricity and heat, meaning boilers may be reduced or eliminated. They can take on the extra power consumption from new medical devices and provide more power than diesel generators alone. Microgrids prove their value beyond merely providing power for essential services during a blackout.

Another business advantage: Microgrids can also be easy on the budget.

Energy as a service

Microgrids can be provided to healthcare facilities through the energy-as-a-service (EaaS) model. EaaS agreements are an OPEX cost rather than CAPEX. The EaaS model allows the microgrid to be highly customized to the hospital’s energy needs, depending on compliance and available energy resources. If the hospital has a goal to reduce its carbon footprint, then the EaaS provider can customize the microgrid to help meet that goal. The EaaS provider can create a hospital microgrid from scratch or customize it to incorporate existing equipment. If the original equipment is too old, it can be replaced as part of the contract agreement. Along the way, the EaaS provider can also incorporate new technologies to improve performance while fully addressing all of the operation and maintenance.

The benefits of microgrids are many. They can increase resilience while also addressing sustainability goals. With EaaS, the risk is taken off of the hospital’s responsibility and taken on by firms that specialize in deploying, operating and maintaining microgrids. Leveraging the outcome-based EaaS model to add microgrids to hospital power systems is the next step toward energy transformation within the healthcare industry.

Lance Haines is the chief technology officer-microgrids at Schneider Electric.