Aloe Terra - Lawrence Tech University 2007 Solar Decathlon Team

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ALOeTERRA is using a solar thermal system known as evacuated-tube collectors in place of a traditional central heating system in our house. Three evacuated-tube collectors, consisting of 20 evacuated-tubes each, capture radiation from the sun to satisfy the needs of both water heating and space heating. ALOeTERRA chose to use the evacuated-tube technology over other solar collectors because of its high efficiency and its low maintenance.

Each of the 60 evacuated-tubes is composed of an outer glass cylinder, an inner glass cylinder, and a copper heat pipe.

The two glass cylinders are positioned outside of the copper heat pipe and act as a double wall vacuum. This vacuum prevents heat from escaping and allows the outer glass layer to be cool to the touch!

Inside the copper heat pipe is a fluid that heats up from solar radiation. Once warmed, the fluid vaporizes and rises to a bulb located at the top of the copper heat pipe. At this point, the heat from the fluid is transferred from the bulb to a manifold. The heat from the manifold is then transferred to a specially designed domestic hot water storage tank.

The domestic hot water storage tank used in our home is specifically designed for a solar thermal system. The tank requires no electricity or gas to operate! Instead, the tank is powered by a transfer of heat from the manifold of the evacuated-tube collectors to a fluid located in the tank's coils. The domestic hot water tank acts as a super insulated heat exchanger, routing the stored heat to provide domestic hot water heating and space heating.

For more information about evacuated-tube collectors visit http://www.btfsolar.com/

The ALOeTERRA home is warm and cozy thanks to a radiant flooring system. Radiant flooring systems provide space heating by pumping a heated medium though an arrangement of pipes located underneath the floor of a home. The warmth from the heated medium is released through the floor and radiates upwards to provide a uniform temperature for the entire house.

In our house, the radiant flooring system, like the domestic hot water system, operates off of heat transferred from the home's solar thermal system. Heat generated from the solar thermal system is transferred to home's domestic hot water tank and then to the radiant floor. Heat leaving the radiant flooring system travels right back to the solar thermal system where the cycle is repeated.

ALOeTERRA designed the layout of the radiant flooring system to be as energy-efficient as possible. Each room was carefully evaluated to determine the maximum amount of heat necessary to stay warm on the coldest Michigan day. This evaluation led to a strategic placement of pipes and the addition of a material called Warmboard. Warmboard is simply an aluminum covered board positioned above the radiant flooring pipes to ensure that heat is distributed evenly and efficiently.

For more information on radiant floors, check out Warmboard

Tips to Keeping Your Home Cozy!

A solar chimney uses energy from the sun to naturally ventilate a building. The design of the chimney is usually specific to the building it is ventilating. More often than not, however, a solar chimney will face the direction that it can receive the most sunlight and will stand taller than the structure being ventilated.

The solar chimney in the ALOeTERRA home is built into the structure of the house and ventilates through a skylight opening. When the sun heats the chimney, the air within the chimney warms and exits through the skylight. As the warm air leaves the chimney, cool air is drawn from below, creating a breezy updraft.

Breathe Easy in Your Home!