More PV Generation

Our next step was to add more PV generation.

With only 2kW DC solar, it took all the daylight on a sunny day to run our modest daytime loads and recover 50% of the energy in the batteries.

Several days of snow was enough to run our batteries down below the threshold where our backup system came on, and it took several more days to recover enough state of charge in the main battery bank for the main system to come back on. We discovered that our battery management system relied upon the batteries being brought back to full every few days, and our 2 kW DC of PV just wasn't enough to do it without a generator.

The other reason we needed more generation was to support additional loads. With fumes from our propane-burning stove, the buildup of CO2 from 2 humans and a cat breathing and talking, and radon seeping through the slab, we needed to add HRV, radon fan, and electric cooking appliances to our daily load analysis.

With 175 mph wind gusts possible, we hired a structural engineer to design the ground mount for our new solar array. Mounting the new array on the ground allowed us to optimize its daily production in the winter by tilting the modules to 55 degrees. No more snow removal needed!

Using a solar pathfinder, I checked the hours the foothill and trees to the west of the ground mount site would reduce our production.

The sky to the SE is wide open, and the mornings tend to be sunnier here as well, so we decided to rotate the array to face SSE instead of due S.

Construction of the array involved digging the foundation with a backhoe, lining it with recycled wood, adding rebar reinforcement, building the frame, and filling the form with concrete.

The pipes pulled out of the fittings in the first 60 mph wind gusts and the installers had to come back and tighten the bolts, this time with a torque wrench!

With the ground mount contributing an additional 6 kW of power, it now only takes about 2 hours to bring the batteries all the way to full, even on a cloudy day. Once the batteries are full, the solar modules are open-circuited since there is nowhere for the energy to go. We have an additional 10 kWh+ per day that we could be using to heat water with a heat pump or charge our plug-in car, if we could get it up the driveway...

Even after a snowstorm, it only takes one 20 kWh day to recover. Most days we are generating around half of what we could, if we had more loads to feed.

For the technically inclined, here's the line diagram for our system, with the ground mount array at the upper right, charging our lithium-ion batteries at the lower right, along with the newer one of the rooftop arrays, via 2 100A charge controllers. The older rooftop array (upper right) is keeping our backup lead acid batteries full via the charge controller on our backup inverter. The main 240V inverter feeds our main breaker panel, with one 120V leg of the panel fed through the 120V inverter, pulling energy from the main Li-ion battery bank. If the Li-ion batteries fall below the backup threshold, the 240V inverter shuts down, and the 120V inverter feeds one leg of the panel, pulling energy from the lead acid backup batteries, while the Li-ion batteries recover. Note there is additional capacity for expansion as we continue electrifying our loads -- we could add another ground mount array instead of the small rooftop array, move it to the backup position, and retire the older rooftop array.

Climate-Friendly Landscaping

Climate-Friendly Landscaping

One of our favorite ongoing projects is transitioning the landscape in our yard to native California plants. When we bought our house in 1984, there were already some native plants on the periphery of the property, including sage, buckwheat, sumac, manzanita, and ceanothus. Up closer to the house, the previous owners had done quite a bit of landscaping with nonnative plants. We’ve been gradually removing the nonnatives to make way for the native plants. We’ve also cleared a small area for fruit trees, leaving only a few large, well-established trees.

Now, native species are well established along the meandering gravel pathways around our house and on the slope that falls away from our front patio. We chose to concentrate on poppies, penstemons, and phacelia grandiflora, all of which are in bloom as we write this (see our photos below).

Using native plants has many advantages.

• Native plants have evolved over thousands of years to adapt to local conditions. For that reason, they’re well suited to our climate and soil conditions.

• Native plants need less water. Once established, they’re also better able to withstand drought than exotic plants are.

• There’s no need for fertilizer. In fact, fertilizing native plants or amending the soil is detrimental to them.

• Once native plants are established, there’s little or no need for toxic weedkillers and pesticides. Native plants are more resistant to attack by invasive insects and diseases. They can also help keep aggressive weeds from overtaking your property.

• Native plants are extremely beneficial to birds, pollinators, and other wildlife. They contribute to biodiversity.

• A native landscape, properly done and lightly watered, has been shown to help protect homes from wildfires.

• Native plants, especially chaparral, are vital for carbon sequestration.

• Native plants are beautiful! There’s an amazing variety of native plants that surpass traditionally landscaped and overly manicured gardens and lawns in beauty and charm.

• Remember, too, that you’re creating not just a landscape but a habitat!

• For us, an unexpected perk of committing to a native plant garden has been the enjoyment we’ve found in belonging to a community of like-minded people. There are native plant groups that hold gardens tours, give advice and support, and offer educational workshops and seminars.

Converting your home landscape to native plants has many benefits, from saving water, supporting wildlife, and sequestering carbon to enhancing your property with natural beauty and even helping to protect your home from wildfire. We’ve found it’s a win-win choice for property owners and the environment.

Notes:

Native Shrubs and Why They’re Essential for Carbon Sequestration

https://www.resilience.org/stories/2019-01-02/native-shrubs-and-why-theyre-essential-for-carbon-sequestration/

Bird-Friendly Communities Why Native Plants Matter

https://www.audubon.org/content/why-native-plants-matter

California Native Plant Society (CNPS) https://www.cnps.org/

"In this new era of climate change and megafires, how can we work with our environment to protect homes, lives, and livelihoods? We can start at home, with native plants." Read more here: Fire-Resilient Landscaping with Native Plants

Here is a video presentation done by Greg Rubin (California’s Own Native Landscape Design) for the California Native Plant Society: Using Native Plants for Fire Resistant Landscapes

The Drought-Defying California Garden: 230 Native Plants for a Lush, Low-Water Landscape by Greg Rubin and Lucy Warren https://www.goodreads.com/book/show/25810726-the-drought-defying-california-garden

The California Native Landscape: The Homeowner's Design Guide to Restoring Its Beauty and Balance by Greg Rubin and Lucy Warren

https://www.goodreads.com/book/show/15079653-the-california-native-landscape

California poppies and giant flowered phacelia line our front walkway.

The giant flowered phacelia (phacelia grandiflora) is an annual herb that is native to California and found only slightly beyond California borders.

Now that we’ve converted to native plants, we have more bird visitors, such as this mourning dove. The thriving plant on the right is white sage.

We’ve found that native wildflowers are especially beautiful against a backdrop of our granite boulders. This is a penstemon.

Multiple native species, all in bloom, give us a field of color outside the house: California poppy, desert marigold, and giant flowered phacelia.

Climate-Friendly Transportation

It would be more climate-friendly for my husband and me to walk, bike, and use mass transportation than to drive automobiles, of course. However, our home is in a semirural, unwalkable area that has limited bus service. Our best solution is to own electric vehicles (EVs). We have solar panels, and we’re retired and home during the day: we charge our cars on sun.

In 2017 we got a Chevy Volt with a 53-mile range on battery and a gasoline engine backup. We bought it at a time when all available EV models except Tesla’s had a range of less than 100 miles. Living in a remote area, we had some “range anxiety” at first, but range proved not to be an issue for us. We’ve rarely used the backup gas.

With our range anxiety eliminated, we took the plunge in 2019 and purchased an all-electric Bolt. We still have both our EVs, but we choose to drive the Bolt most of the time.

The small battery on the Volt allows us to use the 120V charger that came with the car. When we got the Bolt, we installed two 240V, 50A circuits for quick chargers. We bought one quick charger for the Bolt so that we could fully charge the car overnight if necessary. We also use the Volt 115V charger, which my husband has adapted for use with 240V to cut charging time in half.

My husband also built an electric bicycle that he planned to ride the few miles to our older son’s home so they could carpool for the 40-mile one-way commute to their workplaces. Then the pandemic hit, and we all started working from home. Eight months later, my husband opted to retire; now he uses the e-bike for exercise. We live on the top of a big hill, so the assist from the battery comes in very handy!

The advantages of owning EVs go beyond benefiting the climate and helping us reduce our carbon impact. I’m grateful we don’t have to worry about carbon monoxide poisoning and we aren’t polluting the air with lung-damaging fumes, particularly when our cars are idling. In addition, I absolutely don’t miss going to the gas station. We haven’t taken a long trip in one of our EVs yet, but we know several EV owners who have done so quite successfully.

The cars are also a joy to drive! They’re quiet and very quick off the line (not that we would know about that 😉). We discovered another unexpected bonus when our power was cut off during Santa Ana wind events last year: we were able to use the Bolt battery as a power source for our home. It kept our refrigerator, freezer, laptops, and cell phone running throughout the time that the power was off.

We have been driving EVs for about four years now, and we would never go back to an internal combustion engine vehicle.

We’re happy to answer any questions anyone might have about our experiences as EV owners.

Notes:

1. In California, transportation produces about 50% of the state’s greenhouse gas emissions. (https://www.energy.ca.gov/about/core-responsibility-fact-sheets/transforming-transportation)

2. Are you ready to learn more about EVs but aren’t ready to talk to a salesperson (who may or may not have that much knowledge about EVs)? Contact your local Electric Vehicle Association. The EVA is a nonprofit organization made up of friendly EV enthusiasts who are happy to share their expertise with you at no cost. The EVA frequently holds informational events where you can get a close look at EVs, ask questions, and even ride in the EVs.

Electric Vehicle Association: https://www.myeva.org/

Electric Vehicle Association of San Diego: https://www.sandiegoev.org/

3. As an EV owner, I’m frustrated at the false information and propaganda surrounding these cars! Remember that a lot of such misinformation is being propagated by the fossil fuel industry. Here are two good articles that debunk EV myths.

From the EPA: Electric Vehicle Myths - https://www.epa.gov/greenvehicles/electric-vehicle-myths

The 8 EV Myths Everyone Should Stop Believing - https://energy.drax.com/insights/electric-vehicle-myths/