(Continued from Part 1. This concludes the article.)
Resolution and Improvement Plan
Finally, the clouds lifted, more sun arrived, and our power problems dissipated. From that point, we did fine waiting for the utility power to be returned. Eventually it was returned. But I had learned an important lesson: I started hunting for a better charger! Much later, I learned there was a chance that my gasoline “inverter generator” could provide steady enough power to pass for “utility power” and directly power my 48V inverter/charger systems with far more power — but that hasn’t been figured out (yet). What I did find were additional non-computerized 48V battery chargers on eBay, designed for golf cart lead acid batteries. Warning: it turns out they have their own “smarts” in the form of a relay that has to see 48V to begin charging — but I was able to easily rewire around the relay to get around that problem. That skill would turn out to be important, within weeks.
Unfortunately, the hurricane wasn’t done with us…
Family Vacation Home
My wife’s family has maintained a retreat/vacation home for decades in the southern Appalachians. It is a wonderful home, and when we took it over, we did a huge amount of work to upgrade and make it more resilient against risks. It is on the downslope of a significant elevation and hydrology of massive movements of water underground is a crucial hazard to that home — so it has several sump pumps to keep the partial basement from flooding. To those, we added our 2nd solar power system, about half the power of the system at our main home. For the retreat home, we selected LIFEPO4 batteries, which require less maintenance and don’t have exhaust gas ventilation requirements in that jurisdiction. (It has other upgrades and additions for resiliency, but there is no need to spill those beans in this article.)
In any home north of Miami, a backup heating supply seems important. So we had a suitably decorative gas fireplace with forced air heating added to the living room. It was only 5,000 BTU. I didn’t realize that it wasn’t a lot of heat, and the price was quite high, but it kept my wife happy, and provided us with at least a little backup heating. That would turn out to be quite important.
We endured a lot of problems with the installation of that expensive solar power system. When the technicians said it was done (the first time), I simply pulled the main breaker — and watched the house go completely dark! The stunned expressions of the installers matched. This happened not just once, but several times, until they more carefully and thoroughly thought through their entire complicated installation, and all the laws and regulations of the State, which required additional add-on hardware to provide protection for firefighters. Those safety requirements made it much more complicated to simply provide backup power when the utility failed. Finally, they had it working. But I didn’t trust any of their plans at that point. As a result, I went through all the data from the battery manufacturer and set all the crucial voltages and set-points of the battery-based system in compliance with their instructions. Unfortunately, I didn’t test their recommendations sufficiently. At that point, I should have listened to the installers more closely.
Back to Helene
The hurricane turned into a tropical storm as it moved through hundreds of miles, and into a massive rain-maker. Everything on a slope — or downstream from a slope — got walloped. I have never seen such massive movement of entire cars and even houses floated away by the force of water! But when we finally were able to get into the area, I saw school fields strewn with cars and even housing deposited on the banks of streams. There was truly massive destruction by the force of water moving down slopes and washing out road after road, foundation after foundation, bridges and railroad tracks. The water system of a major city was non-potable or non-existent for weeks. Power was absent for very, very long periods of time.
Construction companies’ own buildings, supplies, heavy equipment were not spared, making reconstruction even more expensive and difficult. Churches and small towns rallied to provide water, food, and shelter in any way they could for all their residents. I was very, very impressed by those efforts, both government and volunteer. Radio communications helped volunteer efforts immensely.
We didn’t know before this storm that our house was located physically below a good-sized body of water, higher up the mountain, which we had never seen. As Helene dumped historic amounts of rain, that body of water overflowed, creating a new “creek”….down our road. We’re talking many inches deep of very fast-moving water running a mile or more down the side of a mountain… And a portion of that “creek” diverted through our basement windows. We would not know it for months, but the settings recommended by the battery manufacturer left us with very little actual backup charge, and our pumps failed earlier rather than later — and as a result we had four feet of mud-water in the basement of our vacant house. We got that word from a friendly neighbor, because it was weeks before we could get into the area.
We also have a renter in a different portion of that property. We had taken great care to provide backups for that renter (who has relatively little preparation themselves). With zero utility power in our area, they suddenly fell in love with the little 3kw gasoline generator we had stored for them, the extra gasoline we left, and the transfer switch that allowed them to power the most important parts of their housing, including the blower of their oil-fired heater — they were one of the only ones in our neighborhood with any power for quite a long time!
Our friendly neighbor was able to use that power to get some of our sump pumps going again and in less than an hour we had our basement down to “soaked” instead of “mud swimming pool” — but the water welled up again from the ground for days and days. It was impossible to keep the basement unflooded. But at least now it was clearer ground water, and less mud. So, it was quite a while before we really had our basement secure again.
Living in a Damaged Home
Remember that Hurricane Helene was a very late Cat 4 hurricane, at the end of September, 2024. When we arrived weeks later to attend to repairs, there was basically no heat, and it was now cold in those mountains. Our mud-flooded furnace was completely inoperable. The tiny secondary heater we had added was working….but only for one room. We did have utility electricity then, so we turned on the electric oven, the stove top, and every heater we owned, to get the house to “big-coat-temperatures” for elderly preppers. Not warm, just “livable” while we waited to get contractors in. In that situation, electric blankets were a hugely important item for sleeping!
The heating contractor (whose own building was also basically destroyed along with much of their inventory) explained to us that state regulations meant that any part of our gas heating system that had been flooded, had to be replaced. Hours of work that I had already done in an attempted resurrection of the heating system were wasted. So were many thousands of dollars. Thankfully, it wasn’t long before the old system was torn out, destroyed duct work removed, and precious new heating equipment installed.
The solar power system also had not been installed with a view toward flooding. Some of the system was relatively “low” in the basement — and was destroyed by the mud-water. Sensitive field-effect transistors don’t do well when their terminals are effectively shorted by dissolved salts and silt in muddy floodwater. That was why our solar system could not even recharge when the sun broke through.
Problem: The batteries were bone dead. And you can’t start a LIFEPO4 battery from a solar power system that needs some battery voltage even to know what is the nominal voltage! Thankfully, I had learned my lesson from the first strike of Helene — and had brought up a re-wired golf cart 48V charger that could do a “cold start” on those batteries. With my skills, measurement equipment, and spare gear (“one is none, and 2 is one”) I got the solar power system ready to charge quickly.
The underlying issue
But I had not yet realized the underlying issue. The learning wasn’t completed. Even after we got everything going again and the house back together and all the damage to the landscape repaired, water, power all working again….we didn’t know what lurked. We got a clue when our alarm system quit during only a few hours of utility power loss in the spring. That should not have happened! The solar power system should have kept it going for a day or more. What is going on?
So when we made it back there for the summer, I decided to do the acid test and once again, simply pulled the utility power main breaker to test our total power preparation — and within 90 minutes thousands and thousands of dollars of expensive LIFEPO4 batteries were dead enough to drop out AGAIN! The installation suggested numbers given by the manufacturer were bogus. After a lot of study and review of the complicated “state machine” operation of the solar power system’s various components, I was able to reprogram the various charge parameters for a higher voltage, still well within limitations, but resulting in a larger charge being stored in the expensive batteries. I thus got the system all the way back up to true full charge, measuring AHrs of energy moving into the batteries using a hand-held clamp-on (Hall effect) DC ammeter, over a period of several hours of charging. I followed the progress not only by reading the displayed voltages, but checking actual voltages myself with a digital voltmeter.
Once I was convinced I had arrived at settings that would keep the batteries near full charge, I ran a full test, pulling the power at 2:30 in the afternoon. By 10 PM our batteries were still going strong, dropping only 5% per hour with an intentionally significant load of refrigerator, some sump pumps, and a bunch of lighting and communication radios (400 watts or more, continuous). In the middle of the night I reduced the loading to “survival load” (100 watts of minimal power to run the pumps and refrigerator) — and at 5AM the batteries were still 40% charged.
From the data collected during that run, I had REAL numbers to guide me, numbers that showed the likely true state of charge for both the system’s displayed voltage and for my measured battery voltage with a quality digital voltmeter. The chart is shown below. Based on these data, it was clear that my previous settings hobbled the batteries to a charge in the 30% or less range. No wonder the security system died in a brief utility outage, and the sump pumps failed quickly when the reservoir overflow flooded our basement! We now have a real backup system that could handle even 24 hours of darkness! Even on heavily overcast days, I typically get 2-3 kw Hr of power from my system. That is enough to avoid most problems.
This was a big learning experience for someone with formal training in multiple fields and decades of practice experience as well, who still didn’t recognize the “gotchas” in the supposed backup power systems. Thankfully, I had backup upon backup, so that the main house (which was hit first), could be powered by both solar and even put on a propane generator for large amounts of its structure.
Thankfully, I had renters in place and a very hardworking and generous neighbor to help watch over our distant second structure while we were hundreds of miles away. They benefited too — they were the only people in the neighborhood with access to electrical power for some time! My preparedness was a huge help not only to us but to others — and yet it fell short in more than one instance. I’ve already taken steps to shore up the weaknesses that this freak storm revealed. But this was only the power system. There are probably many other weaknesses that I also haven’t recognized yet!
Learning Points
What are the take-away learning points that would benefit all of us from our experiences being hit twice by the same storm?
- Above all, literally TEST your backup power system and see if it can actually power your minimum necessary loads for the required time until either solar recharge or other recharge is possible. Do not depend on manufacturer claims.
- Have backup heating available if you live north of Miami, Florida! And actually test it on a really cold day and see if it can keep your sleeping area tolerably warm.
- Be aware that many battery chargers have internal relays or computers and will only charge batteries when certain criteria are met. Test them in your realistic scenario (e.g. fully dead batteries, or human-induced variations in drain on batteries) and see if they will provide adequate charging, if they charge at all!
- Move to secondary power systems such as a generator earlier rather than later, if your solar power system is showing signs of strain.
- If your plans include any electrical systems, have at least one quality digital voltmeter available and be very familiar with its use.
- If your plans include significant amounts of electrical power, especially DC power involving batteries, then have a clamp-on ammeter. The cheap ones can only measure AC current (via a transformer effect). The more expensive ones can actually measure DC current accurately by using the Hall effect. That means you can measure DC current in wires without needing to interrupt them! This little instrument is extremely helpful if you have solar power and batteries.
- In our case, we routinely test for actual output power from our generators (not just starting the engine.) Therefore, we have caught failing voltage regulators — always test generators that are part of your plans, for actual output power! Keep spare voltage regulators available for each of your generators — these are commodity devices that only come in a few versions and are relatively inexpensive.
- Learn how to absolutely minimize your power usage to the bare minimum — in our case, preventing flooding by operating suitable sump pumps and hopefully keeping the refrigerator cold — to avoid damage to other important systems or food supplies.
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