One of my goals as an entrepreneur is to build my wealth to the point where I can design a custom home on a large plot of land. This will be in stark contrast to the basic 4 bedroom home I live in today. My current home was built in the 1990’s, in a development with 1,000 other homes, with zero green tech.
This post was written with Florida’s climate in mind. I’ve detailed 9 factors that will make any home more efficient and less expensive to operate. I’m sure more factors will emerge as technology advances, but I’ve only included existing technology here. You can buy all these systems today, and the results are proven.
This home will be equipped with a traditional HVAC unit, as a back up in conjunction with the other factors listed below.
The first factor will be the way the home is sited in regards to the path (perihelion) of the sun throughout the seasons on the year. Mature deciduous trees along the south side of the home will help keep your home cooler in the summer, and when the treetop foliage thins out in the winter more sun will reach the home, keeping the temperature warmer from December to February.
The 2nd factor will be lighter colored roof shingles, preferably white. Lighter colors reflect more heat. Some homeowners might not like the aesthetic look of lighter roof shingles, a compromise might be a lighter tan or brown. Either way the cost of the lighter shingles is exactly the same as the darker variety, but a lighter roof will reduce the heat coming into the home.
The 3rd factor will be a radiant reflective barrier installed directly under the entire roof surface just below the attic joists. There is some controversy about thermal barrier, but if we merely lower the attic temperatures by 15 degrees this will ease the cooling needs of the HVAC system. Even with the shade trees to the south and the lighter colored shingles there will still be some sun hitting the roof and heating the home throughout the day, even from ambient light.
A cool attic means lower costs to keep the rest of the home cool.
The 4rth factor will be a photovoltaic array in the backyard, hooked to a motorized system that tracks the perihelion of the sun throughout the day. Why not solar on the roof? The efficiency of current solar panels drops in high heat conditions, so it makes more sense to keep the panels in the backyard, mounted in an area with sun exposure from early morning to late afternoon. The energy from the photovoltaics could also be used to charge our vehicles, especially when the panels are generating more electricity than needed by the home at that moment.
Of course, the home would still be connected to the local electric utility, but with the goal of only using energy from the grid as a secondary or emergency source of power. There are many power storage solutions out there, mostly based on lithium ion batteries, but being grid connected makes sense until far superior battery technology comes to market.
The 5th factor will be a geothermal cooling system that consists of a series of pipes that extend 100 feet deep under the home site. Underground temps hover between 55 to 60 degrees in Florida, a geothermal system pumps water down to a matrix of coils underground, the cold water is then pumped back up to the house to cool the interior of the home. This is far more efficient than running a standard AC unit.
Residential electricity usage in Florida is 41% higher in the summer months because of the electricity needs of a typical AC unit. The other cooling factors mentioned above (factors 1-3) would passively cool the home, causing the blower and geothermal pumps to run less throughout the day. Here’s what a simplified geothermal system looks like:
The 6th green factor will be energy efficient appliances, LED light bulbs, and motion sensors in each room that will turn out the lights when no one is there. Perhaps this timer could also be set to television sets, computers, or any other electric device that can be shut down when the room is empty.
The 7th factor will be high quality / well insulated doors and windows, keeping the environmental envelope of the home cooler in the summer and warmer in the winter. Part of the discomfort from the heat here in Florida is the high humidity from March to October. A better insulated home will stay dryer and cooler, requiring less electricity throughout the day.
The 8th factor will be a solar hot water heater mounted on the roof. This system will store hot water during the day, to be used in the evening for showers, laundry, etc. In the winter the heated water can be run through the HVAC blower to warm the air in the home as well.
The 9th factor will be a simple water conservation system that collects condensation from the traditional HVAC in addition to rainwater from the roof. This water can be used to water the lawn or any other beneficial plants grown on the site. Here at my home in Florida I keep a bucket under the AC condensation outlet and collect 10-15 gallons of water per DAY in the summer. I currently use AC condensation to water the orchids and plants around our home.
These 9 factors will have to be built into the home, but the additional cost will be offset long term by a minimal electric bill. The home will still be connected to the local electric company, but the monthly electrical bill will be minimal, maybe $20 per month.
The small HVAC unit in the home will act as a back-up to the geothermal and solar heating units, in the event that those systems are not heating or cooling the home enough in extreme weather. This might require a central computer system that monitors all the household systems and regulates the needed energy flow as needed.
In the event of a power outage this home would still stay cool and comfortable. The solar panels would capture enough electricity during the day to run the geothermal cooling system if the weather was hot. The solar heater could be used to heat the home if it was cold (we might have to put on a sweater here in Tampa).
I’d rather have a spacious home with green technology rather than a fancier place with a grand foyer, of a giant ornate staircase, or any of the other ego-driven junk that one finds in million dollar luxury homes.
When you visit my green home in the year 2025 I can show you where you can plug in your car, then walk you through the orchid greenhouse and show you how our geothermal system is set up. Maybe after that we can check out the Tilapia tank and how we use the nitrogen from the Tilapia to grow hydroponic vegetables…..
It’s good to have a clear vision of where you want to go, and when I’m out growing my business I think about all the cool things that you can do when money is no longer a limiting factor.
Benjamin T. Alexander
February 6 . 2017