Creating Your Personal Power Plant
Part 5
Integrating a Battery into the System
Follow along as President Greg Garrison goes solar in this mini-blog series.
In my last post, my solar power plant was installed and commissioned. Now that all the power is flowing, I need a way to control the energetic electrons rushing through the electrical circuits in my home. An Enphase battery system will allow me to do just that — to first capture and then store energy for later use in my home. Without the battery, most of the electrons would end up in the grid providing power to my neighbor’s homes.
Jeff and Farlin, part of Northeast Solar’s trusty electrical crew, are ready — and so am I. As they tell all our clients, integrating a battery into the system is the most complicated part of the installation — but also the most satisfying. I’m excited!
Prior to 2020, one hundred percent of NES’s solar installations were grid dependent and had no storage option. Today, there are several options for battery storage, each using slightly different chemistry, voltage, and technology. Some are safer and more reliable than others. NES only offers one system — the Enphase IQ battery system. Why only one? The Enphase is the safest and most technologically advanced battery system.
95% of our clients, however, do not have battery systems, and still use the local utility as grid storage for the excess energy they produce. Why is this the case? Because grid storage is simpler and cheaper and satisfies the economic benefits that most people expect from a solar installation. Simply — excess energy produced by the solar array is sent to the grid from a solar installation and credited to the homeowner’s electrical account, and then “stored” until they need power from the grid. At that point, the stored credit is used. An appropriately-sized system will have an equal balance of production, consumption, and credits, allowing homeowners to offset 100% of their electrical bill. Eliminating their electric bill is why most of our clients go solar. And it is a GREAT reason to do so. It is better to have local energy dollars in the homeowner's pocket than in the utility's.
I decided to install a battery not only because of the enhanced availability and advanced technology of the current systems, but because of the security and control a battery system would afford as well.
Let’s start with the main reason — security.
When the power goes, out my power stays on. It’s that simple.
I don't know if you noticed, but our planet’s weather patterns are fairly unpredictable — and frightening. As I write this, it is mid-January, and California is drowning under multiple atmospheric rivers; Buffalo, NY is still buried from a once-in millennium snow storm, and people are losing their lives to January tornadoes in the south. What do all of these events have in common — besides freaking me out? Large-scale power outages. Bad storms = no power. A warming climate has increased our collective and individual anxiety about security and grid resiliency.
Adding energy storage to my solar installation reduces my energy insecurity concerns — and might do the same for you. Because I have a home essentials backup system, when the power goes out (which it inevitably will), I will still have heat, refrigeration, internet, and lights, whether I am home or wandering around our planet. This is important to me.
After considering my own energy needs, I chose to install a 10 kWh battery. A fully-charged battery will power my selected circuits for two-plus days. If there are clear skies during the day, the sun will replenish my system, which can then power my house indefinitely. I am fortunate — I don’t need backup power for water, septage (I have town sewer & water), or cooking (I will use my outdoor grill). Households that do have these needs will need a larger battery; Enphase currently offers batteries with 10, 13, 16, or 20 kWh.
Part of the essential backup is selecting the circuits you want the backup system to power in the event of an outage. The best way is to make a list of what is critical, which for most people includes heat, water, septic, refrigeration, and internet. Of course, you will want to include some lights; some people use a power strip for internet modem to ensure additional outlets for other uses. To make sure that Jeff had the correct circuits to wire into the backup panel, he had me go to the circuit location in my house; when he flipped the breaker, if the power went out, we knew we had the right circuit. Jeff then marked it, named it, and wired it to the backup panel to help make everything clear.
The battery can be set for either self-consumption or full backup. I use self-consumption mode, which allows me to store the excess energy from my power plant in my battery and use it later after the sun sets. My excess power only flows to the grid when the battery is fully charged, enabling me to use the grid as a second storage option. Most of the year, the stored energy will power my home all night.
The best thing is that I control that energy. I can use more of the stored energy in my home, or I can send more energy to the grid. It’s my choice.
Since December, my array has not produced enough energy to fully charge the battery during the day. That was expected; days are shorter and skies mostly gray. The battery, therefore, is set to retain a 30% charge and not fully discharge. At 30%, or three kWhs of storage, if the power goes out just after sunset, it will last me the entire night. Again, this is under my control; I can determine what percentage I retain in my battery.
Conversely, full backup mode ensures there will be enough stored energy to live comfortably for many hours. But I don’t have to choose between self-consumption or full backup; the Enphase system has another option called Storm Guard. This feature can be enabled or disabled by the system owner. I have enabled this feature in order to ensure greater security during inclement weather events. When enabled, Storm Guard is activated when the National Weather Service issues a severe weather watch or warning. Once the system receives the alert, a text or email is sent to the system owner, and the battery is automatically switched to full backup. Regardless of the time of day, the battery is prioritized and rapidly charged to full capacity, generally by the grid. Once the watch or warning expires, the battery switches back to self-consumption mode. It's a great feature. It only takes 45 minutes to fully charge the battery from the grid; even though you are being charged by the grid to charge the battery, that stored energy, when released back into your house’s system, would offset the cost. Storm Guard is, however, limited to storm notifications and can’t protect you from a squirrel that immolates itself on the neighborhood transformer, ha.
Power Through The Storm
A recent snow storm caused an outage in my neighborhood. Storm Guard had been activated and my battery was fully charged when the power went out. I felt no disruption except for not being able to use the stove; stoves are one of the highest consumers of energy in the home, so would drain the battery way too quickly. The outage lasted six hours and my battery was still at 93% when the power was restored. It was actually exciting. I went around the house and ensured that all the circuits that Jeff and I had selected were online. They were. I texted Jeff and told him that I had lost power and all was well. He responded — That’s awesome, thanks for sharing. I never get to hear about it working correctly. LOL.
We’ve heard from other customers, too, who fared equally as well when they lost power. I know this all sounds good — and it is — but I’d be remiss if I didn’t share some of the challenges that batteries present.
The first and often most formidable is finding the right place to install them. Local building codes have changed and don't allow batteries to be installed in finished areas, including finished basements. If you have an unfinished basement, you may, depending on the local inspector, install the battery there provided you install a fire-rated room around the installation. You can situate the battery in a garage, but it must be protected from a car colliding and damaging the battery. My local inspector wanted me to build a new room in my finished basement — space I was not willing to give up— and the garage was not a suitable location. So, I installed my batteries outside, on the side of my house, in a custom battery container. This added cost to the installation, but worked out well. My only consideration was extreme cold temperatures. Even though the battery is rated to zero degrees, Northeast Solar installed a heating element in the container that keeps the battery above freezing. We’ve had plenty of sub-zero temperatures in recent years; I didn’t want to take any chances. Another consideration is cost. Unlike solar, there is no real monetary payback — but having battery back-up can protect investments of other kinds, particularly if you have a big chest freezer stocked with expensive farm-raised meats that you might lose if the power goes out. Yes, you get a 30% tax credit from the government for energy storage, and there are utility incentives. Together, they may produce a payback. I chose not to participate in the utility program, because by doing so, I would have had to surrender control of the battery to the utility so they could use my stored energy in their grid during peak demand times — and there is no income guarantee. My payback is the peace of mind and energy independence that comes with being in control of my power.
Finally, batteries are technology driven. It took several days to get all the proper software updates, which, in all honesty, frequently happens with our installs. But once the bugs get worked out, the batteries run error-free, are very reliable — and seem essential these days.
Installation is Complete
Now that the installation is complete, I’m eager to maximize the work that’s been done. Next, Northeast Solar will be installing mini-splits, or air-source heat pumps, which will provide heating and cooling for my house.
This is the next step towards gaining energy independence and utilizing the power plant that I’ve installed — providing me with long-term resiliency, security, and economic independence from energy costs.
