The Lovins house tour was most interesting because of the various house systems; heating, water, electricity, etc. I’m sure there was more going on than what met the eye but what met the eye was pretty exciting.
First, there is a lot of data collected in this house. I would have loved to learn more about the data systems. I don’t know what the Johnson Controls box housed, but they are HVAC products–there was a rack for network equipment and this Davis Weather Instrument Panel.
Apparently the house has sensors like ours did–and the data is collected and recorded from various locations. The new array of solar panels use Enphase microconverters that have data collection built in and a website at EnPhase delivers data about the performance back to the house. A monitor in the entry hallway displays various house data including the solar collector data.
The electrical system is solar photovoltaic and grid tied with a huge battery backup. The battery bank was enclosed in plexiglass and probably vented to the outside. The batteries were sealed lead acid Absolyte from Exide Technologies in a stacked array. The batteries are always kept topped up, however, they are only used in the case of a power outage–I read that they had been used 5 times since the system was installed.
This was labeled as a control panel, with two large conduits leading from the battery bank, it is the DC shutoff.
The system had not one, but TWO Sunny Boy inverters–they explained that this grid tie system overproduces energy for the house during the day and they purchase green wind energy at night to reduce the total carbon footprint of the home’s energy needs.
The radiant heat system was similarly very impressive. They had embedded polybutyl tubing in the floors when the house was built but only put in an active radiant system in 2009. The system is heated by solar thermal panels on the roof and each zone has its own tube in tube heat exchanger so that the thermal panels use glycol while the house system is water. There is a water meter on each zone. Not sure why the water is metered–but the white cylinders are ABB Hygienic Master food quality water flow meters from Germany.
There appear to be shutoffs just before the expansion tank, probably where the heating water enters and leaves the heating system for the zones.
The system has an electric boiler boost from whatever the solar panels are producing to usable hot water.
The plumbing has very few 90 degree angles to eliminate head issues. Although there are also several Grundfos pumps.
There seem to be a lot of monitoring devices on the radiant system too.
A mixing valve with an outdoor reset is used in the system to modulate the temperatures going into the radiant house piping.
Finally an indirect water heater provided household hot water–these have a coil heat exchanger in them that heats domestic hot water–probably boosted by the electric boiler as well.
The variety of lighting systems was very interesting. Most of the house had LED strip lighting for general night time illumination, as well as large hanging fixtures with shades that had circline florescent bulbs in them. Daytime lighting is mostly solar through the large windows and also through a few solar tubes in the north hallway.
More LED track and a line of Japanese Lanterns
Both LED bulb and strip lights were used.
Interesting Frank Lloyd Wright type use of a white translucent material in a wood panel probably to cut the glare on this desk from the direct sun into the solar greenhouse.
We were told a bit about the ventilation system. The tower held an Energy Recovery Ventilator–they called them panel exchange ventilators. I did see one ceiling fan in a high area of the office ceiling.
And the ventilator inlet and outlet seemed to be located side by side in the tower.
In addition to these there were several operable panels on the high north wall opposite the low intake windows of the greenhouse that could be opened with a system of pulleys and cords to vent hot air and pull fresh air in from the low greenhouse windows.
The water system was designed for low use also. I didn’t take photos of the bathroom, but there was a Toto toilet with a tank sink–water from washing hands drains into the tank for the next flush. A waterless urinal, a small hand sink with low flow faucet and a corner shower also with a low flow shower head, although this shower looked decorative and unused.
They mention on the website that the gray and black water systems are separate, although Colorado has been slow to legalize gray water systems and rain water systems are so restricted that collection is not plausible for most people.
So the systems were both relatively simple (greenhouse with vent panels) and very sophisticated–photovoltaic electric system). I’m sure there was more to see and learn but the tour was only a couple of hours long. We both really enjoyed it though!