The rules in our subdivision require that a tank over a certain size (maybe 20 gallons) be buried. Our is over 300 gallons and it is buried. It was no big deal. Excavated the hole when digging the foundation. Poured a concrete pad and inserted bolts. Propane company dropped tank (with sacrificial anodes) into place and chained it down. Hole was backfilled with sand when the house was backfilled. The line runs underground (with safety tape over it so it doesn't get dug up) and there is a very small metal box where the line comes out of the ground and it connect to the back of the house. It's no big deal, a small shrub would completely hide it. The propane company owns the tank (so they say, I never signed anything) and they don't charge for it, but I am only supposed to use them for fills (it's only been filled once in two years). Our utilities are underground and our phone and power meters are on the side of the garage, not highly visible. The transformer is in the woods. The meters and boxes on the house are not bad looking at all. A small metal box for phone and cable, a meter mounted on another metal box with the shutoff for the electrical. They are barely noticeable, but we carely planned where they would go.

Is it possible to have two propane tanks, a main and auxilliary, connected to the 'service' point of a home via a 'switch-over' valve of some sort? Purpose would be to use the main tank all the time but switch over if the main tank goes empty and can't be refilled (emergency).

If you're really sure you want tankless (and you kinda seem to be), I'm not going to argue with you. I'll just say a couple of things and then I'll bow out. Disclaimer: I'm not an expert on these matters. They just interest me and I hope to be more energy independent in the future, so I read up on them. I always welcome corrections from knowledgeable folk. First point: IMO electric resistive heating of ANY kind basically just doesn't play nice with PV, off grid or on. The only time it really makes sense is when you're off grid and your system produces more energy during the day than you can store in your battery. This can also apply to some extent if you're intertied and your utility pays you wholesale or less when you sell your power, essentially penalizing you for conserving. Either way, dumping your excess PV energy into water heaters is one way to store it for later use. However, it should be obvious that to store that energy, you have to use traditional storage water heaters, not tankless. Second point: Peak demand matters. It matters to your electric utility, and it matters to your bill. You probably know more about CA rates than I do, but it appears to me that right now California is more into time of use (TOU) metering than peak demand metering. However, more and more utilities are adopting peak demand metering for residential customers (they've had it for business for ages). So even if you're not dealing with it now, it may well be in your future. Demand based metering watches your power (not just energy) usage. The higher it is, the more you pay for all your electricity. In one demand scheme, you pay a surcharge based on your peak power usage (in kilowatts), In another, the price they charge you for every kilowatt hour you use depends on your peak usage -- the higher your peak, even if it's only once in the month, the more you pay per kWh that month. Let me give you an example of the second scheme. Let's say your house's big energy hog right now is an electric range.. Most of the time, you just use one or two surface units at a time. So your peak demand is relatively low, and you pay (say) 14 cents per kWh most months. But when you cook Thanksgiving dinner, you have all the surface units going, plus the oven, and a microwave. On that one day, you have a much higher peak demand. Your utility takes note. And that month, you pay 20 cents per kWh for EVERY kWh you use all month. So even though that month's usage is only a little higher than usual, the final bill for the month is MUCH higher. Now imagine what could happen to your bill if you add an appliance that increases your peak demand every day of every month. Guess what: when it comes to peak demand, tankless electric water heaters are MONSTERS. Think about it. With its mild climate, California is a great place for heat pump storage water heaters. That's what I'd get if I were you. Not tankless, and definitely not electric tankless. And that's all I have to say about that.

I'm going to respond to you since no one has. I've lived in SW Florida for 20 yrs and have gone thru many hurricanes. This last one, Irene took our power and water out. We get water form the local water co on the island and after a while the water stopped as well. They use brackish well water and do a reverse osmosis. When their power went out, so did our water. We always packe the refrigerator with food, canned goods anything before the hurricane and cool it a notch or so down. The fuller it is, the longer things stay cool. We run a generator with gasoline. we would run it here and there to keep the freezers going and concerve fuel. Not knowing how long we would be without power and without power the gas pumps don't work. All generators will handle X number of items, if you plug too many things in, they can't handle it. Howevere, as it generates electricity, there could be excess power just being wasted. So you learn what it can handle. I know a neighbor down the street from us had a propane tank that was connected so when the power went out, it automatically kicked in and in a safe way (it can be unsafe and can kill the electrical workers working on fixing downed lines). Your electrician should know how to wire things up. We hook up our generator and turn the main power off. It's safe for anyone working on restoring the lines but we don't know when the power actually comes back. We listen the the stillness know that the neighbors has automatically shut off:)) A 250 gal propane tank is HUGE. I would guess you could run on that for a very long time. If when it happens, take a reading of the tank, run what you want for a day and take another reading. It should give you a rough idea of the useage per hr or per day. While you may want to run your well pump, it's also a very good idea to have large containers of water handy. We have those large blue plastic containers for water and the red ones for gasoline. Water is the most precious and is missed the most during difficult times. It's also ideal to have a gas cook top or rangetop that can be lit with a match. I hope this helps you a bit in planning for the worst. Hurricane season is not far away. Semper Paratus as my latin teacher said. "always ready." Inga