Solar PV, Battery Energy Storage, and EV Charging

by Adam Walburger, Frontier Energy DER Expert

As municipalities and utilities begin to shift their fleet vehicles to all electric, they are also considering battery energy storage. BES can keep charging stations operational when the power is out and reduce costs associated with demand charges. However, the costs associated with solar PV and BES can be substantial.

Frontier and our partner DKS Associates are creating year-by-year plans to transition light-duty fleet vehicles to electric by 2030. My team’s role is to model the additional electrical load that car charging adds at facility, and then estimate hour-by-hour energy consumption and cost, including potential demand charges.

Central Garage EV Charging Data Profiles

Most clients have one or two primary overnight parking locations and several additional “domiciles,” each with a handful of overnight cars. Vehicles’ duty cycles range from less than five miles a day to more than 100 miles a day. Therefore, each domicile has a unique energy profile. Some will never draw enough power to slip into a demand charge while others could see demand-setting events several times a day. In areas with pervasive PV installations, utilities’ peak periods are shifting from late afternoon to early evening, which will coincide with charging times as fleet EVs return to their domicile location for the night.

Corp Yard Typical Day DER Operation

With a good picture of energy demand, we review satellite images and building plans to determine if a domicile has enough physical space for PV and long-duration BES. (Pre-COVID we did site inspections, but we’re getting good at estimating roof and parking lot sizes from Google Earth.) Off-site storage is also an option but hasn’t been feasible in any of our completed transition plans. In current projects, our model shows that BES yields a reasonable payback at only one or two domiciles, and not necessarily a primary parking location. BES has the best return on investment at locations at which high-mileage vehicles charge—those that return to base every day with a nearly depleted battery—by time-shifting low-cost PV generation into the early evening hours to offset a portion of vehicle charging needs. Currently BES is a costly option and for most fleet domiciles the more cost-effective approach is to combine load management and behavior change. As prices decline, we expect BES deployment at additional facilities to meet the dual goal of resiliency and ROI.

For many of our clients, though, EV transition is part of a commitment to reduce greenhouse gas emissions and decarbonize their buildings and fleets. Our transition plans to date show that opting for a zero-emission fleet, including BES instead of generators, can reduce annual greenhouse gas emissions from light-duty vehicles by more than 95%.

Interested in how this could work for you? Drop me an email.
[email protected]

—August 25, 2020


The First ZNE McDonald’s

by Richard Young, Director, Frontier Energy Commercial Foodservice

In 2014, Frontier Energy’s Food Service Technology Center (FSTC) partnered with New Buildings Institute and Rocky Mountain Institute to model a zero-net energy quick service restaurant for McDonald’s Corporation. Last week, McDonald’s announced completion of a first-of-its-kind zero-net energy quick service restaurant that uses many of the recommendations in the modeling study.

According to DOE, a zero-energy building has an energy use intensity (EUI) of 20 to 30 kBTU per square foot. A typical office building has an EUI of about 70. A quick-service restaurant, like McDonald’s, has an EUI between 600 and 2,000 due to energy-intensive cooking, holding, sanitation, refrigeration, and ventilation equipment.

A typical McDonald’s has a small footprint and very limited capacity for onsite PV. To get to ZNE status, we had to decrease energy use by 60% compared to a best-in-class McDonald’s. We met that goal by focusing on an integrated design with four strategies:

  • Capturing and reusing waste heat from refrigeration, dish machines, exhaust air, and equipment flues to preheat water and augment the HVAC system
  • Extremely efficient ventilation to minimize airflow rates and the transfer of waste heat to the building HVAC system
  • Sensors and controls to reduce standby energy losses
  • The most energy-efficient appliances for cooking, holding, and refrigeration

Reducing or eliminating stand-by energy consumption is a challenge in commercial kitchens, particularly for quick-service restaurants. Griddles, fryers, ovens, toasters, warmers, and espresso machines need to be hot and ready to prepare the next order even when customer traffic is slow. FSTC-tested appliances that “sleep” when business is slow and quickly ramp the heat back up to serve customers were a key component in the study, and we were glad to see that the ZNE McDonald’s implemented many of these appliances.

Now, more than ever, restaurants need to find ways to reduce energy costs. Every restaurant can significantly reduce their utility bills by using energy and water efficient appliances. Read the results of a plug-load study that Frontier recently finished or contact me to brainstorm ideas for making any hospitality business more efficient and ZNE-ready.

—July 21, 2020

Red Frog: Off-Grid Island Resort

Red Frog resort in Panama - Green Globe certified

“It’s the right time to invest,” said Gerardo Aguilar of MGM Innova Capital. “We want Red Frog to be ready for the turnaround!”

Red Frog Beach Island Resort on Panama’s Bocas del Toro archipelago, was designed in concert with nature. “When we founded it 17 years ago, our goal was to be socially responsible and environmentally sustainable,” said CEO Joseph Haley. “Our first steps were to preserve 80% of the property as a nature preserve and establish a foundation to improve the lives of the people who live in the nearby community. Then we built a beautiful eco-conscious property that has more natural forest than when we started.”

In 2015, Frontier Energy’s Energy Insight team conducted a comprehensive certification process that made Red Frog the first Panamanian destination to be Green Globe certified. “The resort had to meet 340 criteria, including sustainable management, environmental practices, social and economic elements, and cultural heritage,” said Energy Insight’s Tanuj Gulati.

The resort is not connected to Panama’s electrical grid. “We have to generate our own power,” Joseph said, “and as you can imagine, a vacation resort has significant electrical demands.” That’s where Gerardo comes in.

MGM manages private equity funds to implement projects that can mitigate climate change while generating financial, social, and environmental benefits. “We started working with Red Frog and Costa Rica-based Verde O Nada to reduce their need for diesel,” Gerardo said.

Maintaining solar panels at Red Frog
Maintaining solar panels with rain water catchment

“The first step was to add solar and integrate it with the diesel generator to create a microgrid. It reduced fuel by 40%, but solar only provided about 20% of the energy needed,” said Verde O Nada’s Michael McKuen. “Then we worked with Energy Insight to increase efficiency by installing LED lighting, new HVAC, pool pumps, and more efficient controllers.”

Early in 2020, the team started working on the next step of Red Frog’s energy independence by adding 1.7 MW of solar and a 4 MWH battery storage system. “Verdo O Nada already manages Red Frog’s microgrid and the BSS will be one more tool to use,” Michael said. “The BES will substantially reduce Red Frog’s energy costs even as the owners repay the investors.” Joseph added, “These DER assets add value for our villa owners now and in the future.”

When the COVID crisis hit, Panama closed its airport and tourism stopped. The team didn’t even consider slowing down the project. “This is the best time to do it!” Gerardo exclaimed, “The resort is empty, so guests won’t be bothered. The construction workers can stay in the student housing to avoid the boat commute to the island.”

“It’s a heavy financial investment, even in a booming economy,” Gerardo said. “We’re bullish that tourism will return, and our technology will provide clean energy for Red Frog’s owners and visitors,” Michael added.

“There’s no better time to do this,” Joseph said. “We are starting to receive requests for long-term villa rentals. If you’re working from home, why not work from paradise? Long-term, it’s a smart and responsible investment for our resort and for the environment.”

—June 24, 2020

Unlocking Direct Installs in Texas

Karya Management manages 53 multifamily properties throughout the Houston, Texas area. “Karya Management’s philosophy is to create a community,” said Swapnil Agarwal, CEO and founder of Nitya Capital and Karya Management. “We don’t just manage the properties. We incorporate activities like after-school programs and established a foundation to invest in quality of life initiatives for our tenants, employees, and the community at large.”

Karya takes advantage of energy efficiency programs that Frontier Energy administers for CenterPoint Energy. “It helps tenants manage their bills,” said CenterPoint Energy’s Chris Lallier, “and helps reduce the load on the grid and conserve energy.” In the Multifamily Direct Install Program, contractors install LED lights, faucet aerators, low-flow showerheads, and water heater pipe wrap in apartments at no cost to the property owner or tenants.

In late April, Frontier Energy’s Steve Wiese called Karya’s regional manager Suresh Chachlani to discuss shifting timelines for already-scheduled work due to shelter-in-place orders. “We started talking about opportunities for direct install work at other properties and realized that the key to unlocking work was to train Karya Management’s maintenance staff to do the installations.”

“Our three properties in Baytown (Texas) have older, less efficient buildings,” Suresh said. “We expect that most tenants will continue to work at Baytown’s refineries because they are essential workers, but they will also spend much more time at home. We could be proactive with the Direct Install program to help tenants control their energy bills.”

Suresh Chachlani, Karya Management, and Edwin Velazquez, Frontier Energy, prepare to conduct a walk-through audit of a vacant apartment to order materials for a direct install that Karya's maintenance staff will perform.
Suresh Chachlani, Karya Management, and Edwin Velazquez, Frontier Energy, prepare to conduct a walk-through audit of a vacant apartment to order materials for a direct install that Karya’s maintenance staff will perform.

Using the maintenance staff to do the work was a great solution. “Each property is like a family; the employees and tenants all know each other,” Suresh said. “It wouldn’t be like letting a stranger into your home. We can strictly oversee the proper use of PPE and maintain sensitivity to tenants’ needs.”

The Karya team immediately started contacting tenants at all three properties via letters, emails, and phone calls to let them know about the project’s benefits. Karya also communicated that the process would help ensure the safety of tenants’ families and maintenance employees.

In early May Frontier Energy’s Edwin Velazquez led a walk-through audit of three vacant apartments. “We identified thousands of opportunities for LEDs to replace existing incandescent bulbs,” he said. After the audit, Edwin ordered materials and modified the installation plans for the maintenance staff. “Materials are expected to arrive around May 18, and installations in 480 units at three properties should be complete by early June,” he said.

The LEDs will help every tenant reduce electricity loads and lower the electric bills during the hot Texas summer. The project helps Karya Management demonstrate its ongoing commitment to conserving energy, helping the community, and—most importantly—helping tenants.

—May 14, 2020