By Dan Mabe
From the April 2023 Issue
As a long-time advocate of battery-powered landscape equipment, The American Green Zone Alliance (AGZA) has spent years fielding questions from business owners considering electric operations. How much more expensive is the equipment? Is it safe? Where and how do we charge all the batteries? First, business owners must understand that converting from gas to electric does not mean simply replacing gas tools with electric tools. You are replacing your gas tools with an electric system that includes a tool, battery, and charger. With electric, you need all three to function. One breakdown in the system renders it useless.
Today’s lithium batteries will have a Battery Management System, or BMS (see “Charging Electric OPE Safely” sidebar below), and smart chargers which will charge batteries, balance the cells, and automatically shut off when fully charged. There is no need to “babysit” the charger and battery. This means lithium batteries can be “opportunity charged” throughout the day when in transit or on clients’ properties potentially. (Always ask clients ahead of time for permission to do supplemental charging.)
The idea is to just plug the battery into a 120V electrical circuit and let the magic happen. And in some cases, this can hold true. For instance, homeowners who purchased a set of lithium powered garden tools will likely have two or three batteries ranging from 185 watt hours (Wh¹) up to 500 Wh, and chargers that typically pull around 2 to 6 amps from the 120V electrical circuit.
If you are a commercial landscaper or grounds department, however, you may need to charge 10 to 30 smaller “onboard” batteries. These are the ones that slide directly on the tool or “backpack” batteries and have what AGZA calls “umbilical cords” between the battery and the tool. Onboard batteries for commercial equipment will usually range from 250 Wh to 600 Wh. Backpack batteries range from 700 Wh to 1600 Wh.
All onboard batteries will require their own charger, which typically pull 6 to 8 amps each. If a large electric mower is purchased, you will be charging high-capacity batteries up to 25 kWh. While some of the large electric mower platforms (which can pull 35 to 50 amps out of the wall) can charge off of 120V outlets, 240V outlets will provide faster charging.
Managing All Those Batteries
If you’re planning on changing out a large portion of your fleet to electric, you will probably be managing 10 to 15 batteries and chargers to start with. All chargers should be plugged into their own “dedicated” circuits which connect to at least a 20 amp breaker.
Believe me when I say: you need to understand your charging capacity prior to purchasing anything. All of the credible manufacturers make inherently safe chargers for their batteries. It’s not the fault of the manufacturer if people use homeowner rated extension cords and cheap power strips to set up their charging infrastructure.
Yes, it can be quite costly and cumbersome to install 10 to 20 new circuits and add breakers to the existing box or install a sub panel. In some cases, however, this may need to be done.
Another alternative is a “turnkey” charging solution such as the TOWA TOOLS PDM SmartCharger. Richard Ogawa, Owner & CEO of Gardenland Power Equipment founded TOWA Industries and developed the Green Industry’s first power distribution manager. TOWA’s TTPDM120S Power Distribution Manager SmartCharger can be used as a smart alternator that intelligently distributes power agnostically and sequentially to maximize your power supply. TOWA’s PDM is an excellent solution for landscapers looking to maximize their existing power supply, without having to worry about tripping the breaker or alternating their fleet of batteries overnight. It can also be mounted inside a trailer to provide an on-the-go solution, depending on the set-up.
Gardenland Power Equipment is located in the heart of Silicon Valley, where the push to go zero-emissions and all-electric started over 12 years ago with the tech campuses and organizations. “What we were finding was that companies going fully electric were running into a problem with being able to charge all of their batteries safely and efficiently,” says Ogawa. “It’s one thing to find a way to charge 10 batteries and quite another to charge 100+ batteries…. This is why we created TOWA to help provide landscapers with an affordable and scalable solution to transition from gas to battery.”
Stationary Yard Charging
A straightforward way to create an adequate charging strategy is to first spec out your workload with your gas tools. Then purchase enough batteries so the electric tool replacement will produce similar workload productivity. Equate the number of batteries to your typical amount of gas and two-stroke oil used to refuel your gas tools. (How do you do this? Most hedge trimmers, edgers, and saws will have a ratio of one battery to one full gas tank. String trimmers will vary, with an average of two batteries to one tank of gas. Leaf blower workloads can be as high as two backpack batteries to equal one tank of gas. For blowers, we all have to keep in mind battery electric will not be as powerful and a workload production rate of 10% to 40% can be lost depending on the setting and season. For smaller walk behind mowers some manufacturers produce a one battery to one full tank of gas ratio, while others are two to one.)
Charging Electric OPE Safely
By Rod Dayrit
Charging solutions are often designed in close collaboration with battery and equipment manufacturers to ensure accurate charging which prevents premature battery failure and prolongs battery life.
While there are proven safeguards to ensure safe operating and charging, issues can still occur if the battery’s and charger’s quality are overlooked. A battery management system (BMS) is integral to a lithium battery system since it regulates temperature, input and output current, and voltage to ensure safe operation of the battery for the user.
For this reason, it’s critical to buy from manufacturers that value the BMS as a foundational part of the equipment. Selecting the right supplier will make all the difference regarding safety. The BMS should be developed or integrated closely with the battery pack and charger manufacturer since the BMS regulates how batteries charge and discharge. With the BMS, battery pack and charger working together, the BMS monitors the state of the battery and (in most cases) communicates it to the charger. In some instances, the BMS can remotely control the charger parameters for the most optimal charging performance.
At the end of battery life, batteries must be responsibly recycled. Recycling databases, such as Earth 911, can guide users to help them find the most convenient location to recycle their batteries. For instance, the US EPA outlines guidelines and references on battery disposal of a variety of lithium battery-powered equipment.
Dayrit is director of Business Development for Americas and Asia at Delta-Q Technologies and has more than 20 years of experience with design and development in the electrical field.
This workload approach allows for quick swapping out of depleted batteries with fully pre-charged ones similar to refueling gas tanks. At the end of work shifts all the batteries are brought back to the yard and placed on their chargers for the night. Smart chargers should ensure all your batteries are fully charged and ready to go the next morning.
Charging On-The-Go With Solar, Backup Battery Storage & Inverters
For a field charging example, we turn to McCoy Horticultural (profiled in Turf April 2022). Owner Richard McCoy converted nearly all his company’s routine maintenance operations to battery electric in 2017. As of 2023, nearly 90% of the account workloads have been converted to battery electric.
After purchasing a fleet of handheld tools and both small and large mowers, McCoy found he then had to “conceptualize” creating an efficient, on-the-go charging solution to meet his company’s energy needs when out on their routes.
The answer, he found, was to set up a solar trailer. While others had done this and the idea was not unique, McCoy wanted to start from scratch with an experienced off grid solar designer. The result was a high performance 1.8 kW¹ solar trailer with a marine grade system that charges batteries all day long with minimal need to use the traditional power grid. (To learn more, read the “Charging Landscape Trailers” companion piece to this article.)
On a good day the system pulls in about 10 kWh¹ and will provide 10 kWh of storage, which powers all hand tool operations during the day and charges the large 48V mowers overnight. The upfront costs of adding charging infrastructure to the solar trailer were not inexpensive. The system cost around $10,000 for the installation of solar PV panels, two inverters, and two backup storage batteries on a 14′ trailer. But McCoy Horticultural chose to focus on the marketing benefits and the long-term cost savings. “Just one example, we have two mowing crews with two team members each, and these two crews will save around $4,200.00 each per year in fuel (based on a fuel cost of $3.65/ gallon),” comments McCoy.
AGZA was so impressed with the trailer, we asked McCoy to display it at the TOTAL PRO EXPO, sponsored by the NJ Nursery & Landscape Association (NJNLA) and the NJ Land Improvement Contractors of America. The overwhelming interest was shocking and encouraging, and conversations at the Expo were lively, inquisitive, and blunt. One attendee approached the solar charging trailer and declared emphatically, “I’m a resister!” By that, he meant, battery power. Yet 45 minutes later, he was asking how he could purchase a design or if we could build a solar setup for him. Indeed, solar setups could be a key to moving the Green Industry into a safe and efficient electrified future.
¹ A kilowatt (kW), is a measure of energy and equals 1,000 watts. A watt-hour (Wh) is a unit that measures the amount of electrical energy used over a period of time. A kilowatt hour (kWh) is 1000 watt-hours.
The bottom line is that going electric is more expensive due to the upfront cost of battery systems vs. gas and the added cost of creating an adequate and safe charging infrastructure. These costs will naturally range with the amount and scale of electrification. There are pathways to a return on investment (ROI) if companies purchase reputable and quality equipment platforms, and take care of their tools and charging setups. Any programs that can reduce the cost of electric and charging infrastructure can potentially help accelerate ROI’s by years.
Mabe is the Founder and President of the American Green Zone Alliance (AGZA), which is on the forefront of clean technology for the grounds maintenance industry. He has extensive experience and understanding of equipment (gas, electric, and people-powered) and grounds maintenance operations. Before founding AGZA, he served as President of The Greenstation, an advanced electric lawn and garden maintenance, equipment manufacturing, and consulting company. During his tenure at The Greenstation, he helped develop early lithium battery equipment, developed protocols for maximizing work production rates for electric tools, set up and implemented off-grid solar charging for equipment batteries, produced prototypes of innovative electric tools, and created a profitable business model for battery electric operations. The AGZA Green Zone® program is a structured process to convert properties from fossil fuel-based maintenance to low noise, zero-emission maintenance and quantify the beneficial impacts. AGZA also offers Service Pro training and certification as well as AGZA Field Tested Certified (AFTC®) designations for battery equipment. An AGZA Online Electric Workforce Training Certificate Courses offered in English and Spanish at www.sustainablelandcare.org.
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