K4RY Moves Station to Solar Power

Ham radio operators have long known how to run their rigs "off the grid." Operating on alternative power sources such as generators, batteries and solar power is a useful skill, whether for fun or when Amateur Radio is pressed into emergency service. QST readers will remember Kim Owen's, KO7U, June 2006 report of running a Field Day CW station from a hydrogen fuel cell and Randy Koehn's, KC5TIL, Oct 2006 article describing a solar powered weather station.

The Auburn University Amateur Radio Club, KR4Y, made its mark in radio history July 2007 when it took occupancy of the university's Solar House and likely became the world's first amateur station that operates its entire facility on solar energy: radios, lights, air conditioning, and yes, even a complete kitchen and laundry machine.

The Solar House

Solar House

Early morning at the home of K4RY - the Solar House at Auburn University.
[Richard Jaeger, K4IQJ, photo]

The Solar House was designed and constructed through collaborative efforts of the students and faculty in electrical engineering, mechanical engineering, biosystems engineering and architecture departments. The house was entered in the 2002 Solar Decathlon competition held on the Mall in Washington, DC. Ten different competitive events were scored and the Auburn University entry placed third overall, just 0.7 percentage points behind second place University of Virginia (University of Colorado was the overall winner, less than 2.5 percentage points ahead of Virginia).

Auburn University's (AU) team took first place for technical design and was one of five to earn a perfect score on the "Energy Balance" component, which covered three areas:

  1. Using solar energy for typical daily activities including:
    • Cooking meals
    • Using common appliances like a refrigerator or dishwasher
    • Operating a TV and video player
    • Using computer stations
  2. Meeting or exceeding energy demands
  3. Recharging the house battery system

The bottom line is that it is feasible to live off the sun, with energy to spare. The AU Solar House also has the capability to recharge an electric golf cart for local trips.

Thirty-six solar panels on the roof can produce over 5.75 kW under full sun (also called "standard test condition"). Five charge controllers ensure that the panels operate at their peak power point, charging 32 sealed batteries located under the deck below the carport roof. Batteries are connected in series and parallel combinations to yield a nominal 48 V, 800 ampere-hour storage system. Two inverters supply 120 and 240 V ac loads in the same manner as would be done in a conventional house. In addition, two 4-by-8 foot flat plate collectors are used to heat water for the home. A standard, commercially available heat pump system maintains a comfortable indoor temperature even in the 100-plus Alabama summer heat. The house has all the comforts of a nice bachelor's pad, including full size refrigerator, dishwasher, combination washer/dryer, microwave oven, electric range, telephone and DSL service for Internet connectivity.

The house has several energy conserving architectural features. Special prism-filled skylights spread sunlight for natural lighting. Structural insulated panels are used to form the floor, walls, ceiling and roof. These panels yield an R-34 insulation rating for the walls, ceiling and roof; the floor has an R-28 insulation rating. Large water-filled plastic columns placed across the front glass windows are a decorative attraction, but also contribute to stability of the inside temperature by the sheer mass of water.

A Brief History of K4RY

Ham radio station

The Heathkit and Kenwood radios set up in the Solar House. A skylight illumniates the bench.
[Richard Jaeger, K4IQJ, photo]

Auburn University's Amateur Radio history extends all the way back to 1912. Back then, the university was known as Alabama Polytechnic Institute, or API. Miller Reese Hutchinson, an API electrical engineering graduate and assistant to Thomas A. Edison, gave a 2.5 kW spark gap transmitter and crystal receiver to the school. Hutchinson was on hand for the club's inaugural transmission in 1913 (under license 5XA) between Auburn, Alabama and Edison's New Jersey lab. Voice radio came to the club in 1920.

In early summer of 2007, Professors John Hung, KI4NHX, Richard "Dick" Jaeger, K4IQJ and other faculty discussed the feasibility of moving the club to new facilities. John had been using the Solar House the previous year for research and was familiar with its capabilities. Dick approached the Dean of the College of Engineering with a plan to move the university's radio club into the house. With the dean's enthusiastic support, the club moved the Kenwood and Heathkit radios and support equipment from their old clubhouse (a dark 100 square foot closet) into the Solar House over a couple of weekends. Club president Carey Huff, AI4TZ, and other members surveyed the outside area and installed a Hustler vertical antenna and ground radials. The next project is to raise a triband beam antenna on the back porch.

In addition to the Solar House radios, the club operates a repeater elsewhere on campus at 147.240 MHz + (pl 156.7 Hz). When you are in Auburn, come visit K4RY at the Solar House, located on the southern edge of the campus.

-  John Hung, KI4NHX; Richard Jaeger, K4IQJ and Carey Huff, AI4TZ k4iqj@mindspring.com