The mechanical room at Louden Farms.
The mechanical room at Louden Farms.
The mechanical room at Louden Farms.
The mechanical room at Louden Farms.
The mechanical room at Louden Farms.

Milking solar: dairy farm relies on cutting-edge SDHW system

Oct. 3, 2013
Traveling the picturesque Pennsylvania countryside, you’ll find a spattering of dairy farms. Pastoral in setting, some of the working processes and methods these farmers implement hasn’t changed much over the years, or so they’d like you to think.
HALIFAX, PA. — Traveling the picturesque Pennsylvania countryside, you’ll find a spattering of dairy farms. Pastoral in setting, some of the working processes and methods these farmers implement hasn’t changed much over the years, or so they’d like you to think.

Located on the outskirts of Halifax, Pa., family-owned Lauden Farms boasts to be the largest dairy farm in Dauphin County, with more than 1,800 sprawling acres of land. With approximately 1,300 dairy cows, workers on the farm milk twice a day — all day — to ensure that they keep up with the increased demand for dairy. You see, Lauden Farms supplies milk to The Hershey Co., home to the ever-so delectable Hershey Chocolate — Hershey Kisses and Hershey Chocolate Bar, for example. And if that wasn’t enough, Lauden also contributes dairy products as part of the Land O’ Lakes cooperative.

Working with livestock, maintaining sanitary conditions is always essential. What can be done with expensive chemical solutions, the farm looked to a cheaper hygienic alternative — hot water. And, with 350-500 gallons of hot water consumption per day, the farm was looking for alternative means for fuel savings. Lauden owners looked no further than a solar domestic hot water (SDHW) system to offset the high price of fuel oil. Now Lauden Farms boasts one of the most cutting-edge solar domestic hot water packages. Solar thermal pre-heat results in approximately $1,600 savings per month or an equivalent 50% reduction in oil consumption.

The owners called upon EarthNet Energy, Chambersburg, Pa., for their solar solution. EarthNet Energy is an American manufacturer of solar thermal systems used for solar hot water heating and cooling applications in the residential, commercial, agricultural and institutional markets. The solar hot water evacuated tube collector features a virtually perfect vacuum. The ENE 24 tube collector captures 92% of the sun’s energy making it very energy efficient.

“These are the highest output solar thermal tubes in the world, period. In fact, the EarthNet solar arrays feature evacuated tubes developed by Daimler-Benz Aerospace,” said Scott Albrecht, owner of Thermocat LLC, the solar installer at Lauden Farms, and energy auditor for the region. A complete collector package includes the collectors, a solar expansion tank control module, a dissipation kit, valves and accessories, and makes for easy installation, which offers a practical renewable solution.

Installed in December 2011 and completed one month later, 10 ground-mounted, 120-ft. wide solar collector arrays provide nearly 500,000 BTUs on average per day. When water initially enters the solar system temperatures average 55°F-60°F degrees, and with the assistance from the SDHW system, temps will average 140°F. With the assistance from a U.S. Boiler/Burnham boiler, which runs at 85% AFUE and provides proper Delta T, temperatures will increase to the preferred 175°F for adequate sanitation. The solar loop consists of half water and half glycol along with Webstone purge and fill valves for complete system reliability. The valves carefully adjust flow and relieve air and pressure as the system fills with the water and glycol mix. These purge and fill valves get subjected to extreme pressure and temperature variations, especially in these latitudes.

“The Webstone products have worked flawlessly under such temperature variations,” said Albrecht. “Temperatures can fluctuate from 32°F to 375°F within less than an hour in harsh conditions. With this, expansion and contraction can occur, yet there are never any leaks.”

ProPal purge and fill valves simultaneously drain, flush and refill any hydronic system, solar or closed-loop system. The three-way ball quickly isolates the flow between the two hose connections, diverts flow out of the system and allows new fluid to be introduced through the remaining connection. Other valve features include a T-pattern flow path, which quickly and easily prevents the flow between the two hose connections; as fluid is introduced into the system, the existing fluid or air is diverted out of the system through the remaining connection; reversible handle for added versatility. “The Webstone products are fantastic. They make life so much easier,” said Albrecht.

In fact, EarthNet Energy solar packages include many Webstone products, including mini ball valves, purge and fill valves, Isolator valves, and pump flanges with and without a drain. “Webstone is a recognized name and it is a quality product. Our arrays look more important in the eyes of the consumer when using Webstone,” said Brian McNew, president of EarthNet Energy.

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