Builder Designs Houses That Can Run For Weeks Without Power

Hunters Point was no more than an idea five years ago, dreamed up by the passion of Marshall Gobuty, the president and founder of Pearl Homes.

Gobuty dialed in on a piece of waterfront land on the Gulf coast of Florida to prove that sustainable, smart communities are possible, which he did to produce a case study for other builders to bring to scale.

After many starts and stops, his company was able to deliver the highest level LEED certification on the model home, called LEED platinum, along with LEED Zero certification. This certification, managed by the US Green Building Council, puts Hunters Point on the path to be the first LEED platinum LEED Zero community in the country.

“He never quit no matter how hard the situation was in that market, he just didn’t stop,” said project partner Blake Richetta, who is the chairman and CEO at global energy storage company Sonnen. “His work is amazingly important, a prime example of trailblazing and pioneering. He has had a more difficult route than any of the other projects we have worked on, and because of his unyielding resolve his customers will get clean, reliable energy.”

And Richetta speaks from experience. His company is no stranger to innovative projects. Sonnen has partnered with many other developers and utility programs, mostly in the mountain states and on the West coast, supplying more than 2,500 homes with its clean energy products.

About the Community

Hunters Point was developed by Pearl Homes as a community of 86 solar-powered, net-positive homes.

“We are excited that instead of expelling eight tons of C02 annually, our homes will positively impact the environment,” said Gobuty. “What we are doing has not been done—living clean, breathing quality air, having all the technology at your fingertips on your app, to know how much of your home you self-generated this day, week, or month. Our homeowners can say they self-generated 98% of their power, which is amazing.”

Pearl Homes used the ANSI/RESNET/ICC Standard 301-2019 CO2e Rating Index to quantify the homes emissions, which showed zero greenhouse gases for the community. This standard is very comprehensive, including non-carbon greenhouse gases, like methane, in the calculation.

It also uses an hourly calculation, versus the more common annual calculator. Hourly calculations are made by bringing together the National Renewable Energy Laboratory’s projections with the energy usage data that Pearl Homes gathers in the HERS Index. The HERS index score for the Hunters Point home is -13, whereas a new home built to code has about an 80 or 90 HERS rating.

“Hourly calculations are critical when calculating greenhouse gas emissions,” said Gary Carmack, who serves as the energy development officer at Pearl Homes. “It isn’t just the amount of the emissions, but also the time of energy usage that has an impact.”

Every Hunters Point home comes standard with a Sonnen energy storage system to harness and distribute the home’s solar power, which is the heart of much of the all-electric community’s innovation.

Carmack describes some of the other systems that are specified in these homes to help reach the net positive energy goals. Homes have a Mitsubishi hybrid HVAC ductless mini split system on the main floor combined with a ducted system on the second floor with a single condenser that uses very low amperage due to the solar design.

He also worked to the specifications of the Environmental Protection Agency’s (EPA) WaterSense program that guarantees the home is 30% more efficient with the design of and use of water distribution.

To meet the net zero qualifications, the home must be designed to be very tight, so it is built with structured insulated and taped ZIP panels, along with an additional six inches of spray foam insulation. While the extra insulation helps the mechanical systems perform, it also means that the air exchange is critical. So, Carmack also chose the Broan-NuTone Overture product that measures and records indoor air quality inside the house, including detecting humidity and particulate matter, and the system will automatically open a vent system if anything is not within ideal range.

This solution, along with much of the rest of the home design, is actually a step beyond what is required by EPA codes, which is unique in a state that is not as progressive as others in advancing these technologies.

Getting Local Support

As a global company, Sonnen has worked with all sorts of partners to bring the value of its solution to reality, some more willing than others to collaborate.

“The state of Florida has not been a very straight forward place for the work or embraced his innovation,” Richetta said of Gobuty’s Hunters Point project. “The utility can be a major part of the solution, and FPL is not against it, but not encouraging it. Whereas Rocky Mountain Power is passionate about the energy transition and embraces these types of projects.”

Despite the challenges, the Pearl Homes team coordinated early on the project with Manatee County, where they received a good deal of cooperation.

“Manatee County took an aggressive approach and asked us to share our designs and plans with them,” Carmack said. “The head of the department for inspections and building has been engaged with us since we started. We have made so many changes, as the home has evolved, that we would be in a difficult position had the county not been so engaging and wanting to help us create a LEED ZERO community.”

Currently Manatee County doesn’t have building code that is even close to what the project is delivering, and Gobuty is encouraged that this project will help them redefine building code for higher performance.

“For example, for door blowing tests, the county requires 7.0, and we come in just above 2.0,” Carmack said. “Normally, the governing bodies, don’t support, or help, but they have been really engaged from before we started. As our concept evolved they worked with us to understand how much different than code our home is. They get it, they appreciate it, and most of all, they are supportive of our vision and are assisting us rather than simply taking the easy path and saying, sorry we don’t have a classification for this home, which is the fact.”

With the diligence of the developer and the county, the project has been able to showcase how zero energy housing can contribute to increased value, sustainability, and health in the community. Making the project come to fruition in such a difficult environment will be hailed as a great asset to the industry Richetta believes.

While the utilities and building codes are challenges and opportunities at the same time, there are some existing challenges that make these projects enormously difficult.

“It’s really impossible,” Gobuty said. “What we are doing in the best time can be a challenge, but do what we are doing in this environment, and it’s very difficult to say the least. I can’t stress to you how much the labor and material markets remain out of control.”

And those challenges add to the bottom line.

Making Dollars and Sense

As part of creating a legacy and prepping his innovation to go to scale, Gobuty had to focus on the affordability of the homes. Currently, the 3,300-square-foot homes net out to a cost of around $375 per square foot, putting them above what real estate research firm Redfin reports is the average cost of $258 per square foot in Manatee County.

With the higher costs, also comes a better, more efficient design that saves loads of carbon from entering the atmosphere, and that drives energy savings into the owner’s pocket.

Based on Florida Solar Energy Center software, a code-built home, the same size of a Hunters Point home, that is connected to Florida Power and Light (FPL) would consume energy valued at about $1,800 per year.

So, at Hunters Point, $1,800 will be saved annually by a homeowner, which at a flat rate after 15 years would add up to $27,000. However, the average annual utility increase from FPL is approximately 2.8%, so when a homeowner would be saving $1,800 in year one, that would increase to $2,800 annually by year 15. With that projected compound growth rate, the actual savings in energy costs in a 15-year time period would be around $35,000.

Other financial considerations include the tax credits received during the year the owner closes on the home. For 2023, a Hunters Point buyer could receive a 30% tax credit on the battery and the solar install. Those two systems cost a total of $45,000, delivering a $13,500 tax credit.

The Hunters Point innovative home design currently costs more, but maybe that isn’t all that important based on home buyer sentiment.

Research group Parks Associates published a report in 2022 in collaboration with SmartThings that stated that 54% of US internet households think their electric bills are too high. Plus, 56% of them would select renewables as an energy source if costs were the same, while 36% would pay more to use renewable energy.

Energy costs are currently fairly inexpensive in the US, where the average residential price for electricity per kilowatt hour is 13.84 cents. This fluctuates state by state—Florida is at 11.58 cents, while California and many East coast states are at or above 20 cents.

While grid power is more expensive in some states, some of those same states are more aggressive in supporting off-grid solutions. As Carmack explains, there are as many as 20 states that have adopted pure metering to allow homeowners to monetize home batteries, putting housing in the position to operate exclusively on solar and batteries.

Right now, Hunters Point has net metering, which isn’t optimal, but at least matches the payment to generation.

“If we generate 100 kilowatts at 10.00 cents per KW, and we bought 100 KW at 10.00, then the owner gets the full credit,” he said. “Whereas last year, the owner would have paid 12 cents per KW, and only been credited 2.0 cents per KW.”

In very progressive California, Sonnen is better able to monetize products for the homeowner, giving checks as high as $78 in one month.

“While that was an outlier, the expectation is to see about $150 to $300 per year of grid service revenue,” Richetta said. “There are two benefits with the storage – reduced energy costs and then the grid service check as well.”

Today, although Hunters Point is reducing electric bills through solar, there is a lot of potential for additional homeowner and community benefits with a more proactive relationship between the community and the utility.

“As far as financials go, there isn’t grid service revenue today, and we don’t have price signals that will lower the electric bill,” he added. “There aren’t mechanisms in place to help align what is best for the pocketbook and what is best for the environment.”

This Grid Isn’t Going Down

Another admirable goal of the project is to identify how local governments can incentivize development strategies to improve resilience in storm events while protecting natural resources.

So, not only does the energy storage design have financial and environmental benefits, but it also provides resiliency in a geography very prone to needing it.

“Hunters Point has back up power, energy security, and that looks very much like a microgrid and could leave the rest of the grid behind to do its own thing,” Richetta said. “Marshall (Gobuty) wants this incredible asset to be used for the betterment of the state.”

Since the homes are designed to create more power than they consume, the excess energy is stored in a battery in each home, and the battery powers the home every day after sunset.

“The homes were able to run on solar even during hurricane season with no sunlight,” Gobuty said. “They were able to run for two weeks without the grid. The standing seam steel roof costs materially more money, however it paid off when the hurricanes came by. During Hurricane Ian and its almost 100-mile-per-hour winds, and no power on anywhere in an area of a mile, our house lit up and was generating more power than the owners would have consumed.”

With hurricanes and other violent storms, this can be a huge asset to the homeowners in this area. According to a blog on Cooling Power Corp’s website, the leading cause of power outages in Florida is natural disasters, like tropical storms.

The number of annual power outages in Florida is about average, which means that there are between 51 to 100. Those power outages last on average 66 hours, but in some places, that can quickly escalate to weeks without power when there is a major hurricane. With more remote workers and with more homeowners choosing to age in place, these power outages can be critical.

The community is exceptional for its design and innovation, and regardless of the needs for resiliency, a great model for anywhere in the country.