Green consultant outfits Encinitas home to save energy

With the flick of a switch, water from Dadla Ponizil’s shower nourishes the backyard macadamia tree.

Ponizil has a graywater pump system, letting him divert shower and laundry water otherwise destined for the sewer to a tank that feeds irrigation lines. Ponizil and his wife, Judy Berlfein, use biodegradable soap, allowing all the water — about 30 gallons per shower run — to go to the garden.

“It’s a shame to waste all of that good water,” Ponizil said.

And that’s just the tip of the energy-efficient iceberg when it comes to their 2,100-square-foot home, which was featured on a tour of North County eco-homes a few years back.

An engineer-turned-consultant specializing in green construction, Ponizil began remodeling the house a decade ago with efficiency in mind. Most noticeably, solar panels atop the roof soak up the sun and create energy. But subtle, eco-friendly touches like clay walls are apparent, too, upon closer inspection.

“Unlike paint walls, American clay is like a sponge,” Ponizil said. “On days when it’s very humid, it absorbs the moisture, so it’s less humid. When it’s dry, the walls release the moisture. It’s a balanced humidity level.”

The home’s electricity bill in October was negative $33. The gas bill that month: $3. And his most recent water bill, covering two months, came to $24.

Ponizil is frequently asked how long it will take the savings from low utility bills to recoup the cost of the solar panels and the home’s other green infrastructure. His answer: Difficult to say, but potentially a few decades.

Regardless, in his view, the investment is worth it to combat climate change.

“The low costs we’re paying for energy don’t reflect the societal costs of pollution,” Ponizil said. “I’m all about internalizing costs.”

He added: “Old methods of home construction are a major source of greenhouse gases that contribute to climate change. We can slow this.”

Ponizil said costs for green upgrades vary greatly, depending on the home and just exactly what’s being installed. Graywater systems, for instance, run from $700 to $3,000 for materials and installation, according to Greywater Action, an advocacy group.

Next to the rooftop solar panels, a solar water heater collects the sun’s rays, warming up the kitchen and shower water.

“It’s cut our natural gas use a lot,” Ponizil said. “Water heating is the biggest part of a home’s gas usage throughout the year.”

And rain falls from the roof into rainwater harvesting barrels at the edge of the home. In turn, this water flows to apricot trees and other produce in the garden.

Under city rules, rain-harvesting barrels can be installed without a permit. Graywater systems fitted to washing machines typically don’t require permitting, though systems for showers do.

Graywater doesn’t include water from toilets, kitchen sinks or dishwashers, because those sources have high bacterial counts, rendering them unfit for irrigation, city rules state.

One efficient home feature came about by accident: The windows of the home’s addition face south, called “passive solar heating.” This allows the addition to capture the sun’s energy in the fall and winter, reducing the need for a conventional heat source.

Ponizil said he was just getting into green construction when the addition was built, so he had yet to learn how home orientation can make a big difference in natural room temperature.

To keep the addition cool in the spring and summer, an outside curtain blocks the sun.

Although the home is a model for eco-friendly improvements, Ponizil wants to go a few steps further. Notably, he wants to retrofit his roof with cotton insulation.

“In most homes the air blows right through the insulation — it’s inefficient,” Ponizil said. “Adding another layer will help save energy.”

For those who want to learn about graywater systems, the Solana Center for Environmental Education in Encinitas is hosting a workshop from 4 to 5 p.m. Feb. 1. Rebate information on rain-harvesting barrels can be found at www.socalwatersmart.com.