The awnings on the south side of the Welcoming Center are actually an array of solar thermal collectors that, as the name implies, absorbs heat from sunlight. The thermal energy collected from the sun is used to heat water for the kitchen and bathrooms. The thermal collectors consist of glass tubes with aluminum pipes running through them. The tubes are evacuated to prevent heat loss during the winter, and the aluminum pipes have a special coating on them to help absorb specific frequencies of sunlight. The entire array consists of eight panels, containing six evacuated tubes each.

A heat transfer medium called "Downfrost" runs through the aluminum pipes at about 1 gallon per minute, absorbing large amounts of thermal energy and becoming very hot. "Downfrost" is a non-toxic antifreeze, consisting chiefly of propylene glycol with a small amount of inhibitor, dipotassium phosphate. The FDA generally recognizes both of these ingredients as safe as food additives, making "Downfrost" a safe and appropriate heat transfer medium for potable water. In other words, if the system breaks and for some reason and some of the fluid gets into the water system, no one will be harmed.

The heat is transferred to the potable water via coils in a water tank. After leaving the solar thermal collectors on the south side of the building, the heat transfer fluid runs into a heat exchange coil in the bottom of a large water tank. There is a second heat exchange coil in the top of the tank through which the potable water runs. Water is heated by the first coil in the bottom of the tank, then rises to the top of the tank and heats the second coil. Water will be 55º F when it enters the top coil and will exit at about 125-128º F, with a flow speed of 20 gallons per minute if all the faucets in the building are turned on.

The diagram below illustrates the heat exchange path in this system.