Heimhenge is the residence of Dan and Sandi Heim, and the base of operations for Heimhenge Enterprises and the weekly blog Sky Lights. We are located in the town of New River, a small community 30 miles north of Phoenix, Arizona. Our home is a state-of-the-art example of energy efficiency. By using passive and active solar design, earth sheltering, and energy-efficient appliances, our energy demand is reduced to half that of a comparably sized conventional structure.
The photo above shows Heimhenge as seen from the southeast, its only completely visible elevation. The west and north walls are earth sheltered to a depth of 8 feet. Contact with this “deep rock” helps cool the house in summer. In our Sonoran desert climate, the energy required for cooling represents about 2/3 of the total annual load. Heating in the winter is provided mainly by passive solar gain and the large interior thermal mass.
Solar cells currently provide 3.5 kW of onsite generating capacity. Our deep-cycle battery storage system holds 12.24 kW-hr of uninterruptible power. To put this in more concrete terms, in the event of a grid power failure, a single 20 amp circuit could be used to full capacity for about 5 hours. In practice, with only critical loads running (smoke alarms, security, telecom, lights, fridge, microwave, ceiling fans) we have 3-4 days of power. We can last even longer if the Sun is shining.
Heimhenge Enterprises itself operates entirely on solar power. Our home office was the first of three circuits activated, and has been running on free solar power since May of 1998. In compliance with the law of conservation of charge, all electrons are recycled. To learn more about our energy efficiency features, check out the links below.