Solar/battery powered inverter generators.

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Anyone have any experience with solar here in Western Washington? My weather station measures peak daylight during December at around 50 to 60 watts/square meter. Last time I looked at solar panels, they were around 18% efficiency. Collecting a kilowatt-hour per day during the winter months would take somewhere around 25 to 30 panels. But perhaps someone here can correct my numbers?
 
There were reports a few months ago that CATL expected to start shipping sodium-ion batteries before the end of 2023. Has anyone seen any more concrete news about them?
 
A zombie thread come back to life.

With respect to a backup generator, your peak loads decide how large of generator you need. If you have domestic well, that usually sets the size as typical well pumps have large starting loads. If you are on public water, the generator usually can be smaller as long as the homeowner, rotates the loads on and off to keep below the generator capacity. Many folks have gone for days with a Honda 2000 watt generator as long as they do not have 240 VAC loads (typical US loads are 120 VAC so someone in England would need to buy a English spec unit rated for 230 VAC 50 HZ).

With respect to Washington State solar, I suggest buying a copy of Solar Power your Home for Dummies and then read it and understand it. If you really want to skip a step, go on the web and look for PV Watts. It can give you a reasonable guess on your yearly production based on local climate models but I do caution you that the program is using a database of solar readings taken around the country and if you not near one and have local weather patterns that cause more or less full sun exposure, the results may be off. The key with solar is you need bright sun, overcast skies will generate some power but far less than full sun. You also need to review local incentives and net metering rules as a solar friendly utility with good state incentives can make a marginal system worth building. Alternatively, a solar unfriendly utility with crappy net metering policies can hurt a home with good solar potential.
 
Net metering used to be a big deal in WA state, but the incentives have now timed out. Is this with Puget Sound Energy? If so, 10¢/kWh net metering.
 
The book is dated but the terms and concepts have not changed significantly. Really the only major change for most grid connected systems is the Rapid Shutdown Requirements for occupied structures. For unoccupied structures or ground type mounts no need for RSD and most folks are using string inverters. If you want to wade into batteries, that is new and evolving. and anything published would be out of date rapidly.

One other big change for the worse is many manufacturers have gone to web based interfaces where the system data and diagnostics are out on the web somewhere rather than in the equipment. Many systems end up with communication issues that require the installer (if the are still in business) to diagnose and reset the communications rather than the owner being able to troubleshoot.
 
I get power from PSE. Costs about 11¢ to 13¢ per KWh, so 10¢/KWh doesn't look so bad. During the summer I might do well with net metering.

I'm more interested in sizing backup power for winter. I don't have my notes handy, but I vaguely remember needing to collect somewhere around 4 to 5 KWh per day for refrigeration, septic pump, well pump, and small other loads. If the rest of my vaguely remembered numbers are close to correct, then that doesn't seem feasible in Western Washington during January. I haven't looked at solar power in several years, though, so I may be misremembering, or the current tech may have improved enough to matter.
 
I got the cheapest genny I could. A two-stroke 800W model from Harbor Freight. For like $100. I followed the manual (purging the carb on shutdown) and never had a lick of trouble. Had to clean the plugs every 20 hours of runtime, but I happily powered a family of 4 through a week after an ice storm once. Running my fridge, stove blower, lighting and small electronics.

So the cheapest option is one of those guys and a propane camp stove to cook on.

similar to this:
Amazon product ASIN B07TWQ8B1S
This is why I am down on the Jackery stuff... I can get this genny, a Jerry can, and a propane camp stove that will cover my needs for a week for less than the cost of a mid-size Jackery thing that will just run my lights for one day or my fridge for several hours.
 
That works and it's why we have a small genie, but it's a gas/propane unit. Propane stores so much better than gasoline. Our cooktop in the house is also propane. However, if the house depends on electricity for a well and/or pump-up sewer system, that requires more power.
 
Hello. We have reverted back too tenting after having a campervan for a couple of years. We were lucky enough to get away in the tent a couple of times last year and the only thing I really missed was the solar panel for charging up phones etc ( we tend to prefer the sites without ehu). So, being an optimist about getting away this year I am planning ahead and going to get a folding solar panel ( looking at about 100w). My my question is, is it better to attach the solar panel to a leisure battery or a generator. We assumed a battery, but now we are looking at the solar panels online and they seem to be "linked" to a small generator. Is this a better option, are they noisy ( i have memories of my fathers generator, and it was like motorbike revving
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)?
I'd be grateful for any recommendations on a solar panel or any views on whether i should have a battery or generator.

Solar generators normally have fans to keep the batteries and BMS (battery management system) cool. The fan doesn't run all the time, and ambient conditions (air temp / humidity) play a role in how often and how long the fan runs. The fans are in no way as loud as a gas or propane generator though.

I have a couple of Bluetti AC180's, an Ecoflow Delta 2 Max (D2M) and an Oscal 700. None of them are loud. I like them all and they perform different functions. The Oscal 700 is the one I use to charge devices, but it has an oddball solar hookup (and they don't include the cable), so I actually charge it from one of the other systems.

Even when only planning to use for charging devices, I would go one size bigger than what you think you need. Because you will always find more uses for it than originally intended. And, keep in mind that the useful (versus stated) kwh rating will be reduced somewhat by fan and BMS activity

Regardless of the system you buy, I would go with the largest portable solar panel that 1: will fit in your vehicle and 2: that has station has the capacity to accept (VoC and watts). That will help account for any cloudy days. Also, you are doing good if even in ideal conditions, the panel produces 75-80% of its rating (those ratings are under ideal conditions, including cooler temps). It has been wicked overcast here in New England for the past couple of months and even my 350w portable panel at times only produces 20-50w because of conditions. If it can get full sun, it jumps up to 300w or more.
 
I guess I would not want to overspent on capacity. It doesn't take a lot of watts to charge a phone or a small lantern.

I'd just get a small foldable solar panel with a USB plug, rated for 2+ amps, and a large-ish USB power-bank. Park that combo in the sun for a few hours, and use the portable bank to charge your devices. Well under $100.

There is a cycle loss going solar to power bank to device, so a lantern could be charged directly (since it wouldn't be needed during the day). For this, it might be nice to have a bigger panel with 2 USB's out.

I got a 4A folding panel on sale a couple years ago for this purpose, I think it was $40?

Flip side: a larger panel will charge your devices in less time, good for partly cloudy days or when the sun is only out for an hour or two...