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7

If you're in the northern hemisphere, the lower angle of the sun in the winter is probably contributing to your low numbers. (When the sun is low in the sky it passes through more atmosphere to reach the ground.) Presumably you'll do better in the summer. Also, the tilt angle of the panels should be matched to your latitude. If your panels are mounted on ...


5

You have fifty-six 240-watt modules. They each produce 240 watts under standard test conditions (STC). STC is defined as 1000 W/m^2 of irradiance, 25ºC temperature and AM1.5G spectrum. These conditions are rarely reached outdoors. If the temperature is higher or the irradiance is lower than STC, you'll get less power. You can usually only achieve 25ºC ...


5

A common design in my area is a heat exchange tank upstream of a traditional gas or electric water heater. They use ethylene glycol (antifreeze) that circulates by thermosiphon action from a solar panel to the tank. The illustration below shows a more complicated (with pump and controller) version. So, you heat a tank of water with a coil full of antifreeze ...


4

If you are OK with manual transfer operation, what you're after is called a "select circuit" manual transfer switch -- they're pretty readily available, for anywhere up to 12-16 circuits. Reliance and Generac both make them.


4

You have the basic concept down. Your challenge will be sizing. What's the minimum possible load you can put on the system? For instance, don't use an inverter to run lighting. Run the lighting direct off 12V, and there's a huge variety of 12 volt LED lighting: from screw-in bulbs, spot or flood lights, LED strips that let you freestyle your lighting, ...


4

Typical grid connected installs of solar panels on homes need a couple of items to get them to work (it's not just lets slap some panels up there and wire it into the house). Solar panels are DC (direct current), your house is AC (alternating current), so a inverter is needed to create the AC current. Also that AC current needs to be synced to the same ...


4

The Powerwall is/will be based on the lithium ion battery technology used in the Tesla cars, so instead of a few large lead acid batteries (like in PV battery banks) it will contain a zillion tiny 18650 cells, which work better if you put them in series and let the voltage soar. This keeps the current low while still allowing the same amount of power output ...


4

I have been an avid recycler in the Portland, Oregon, area for decades. Portland is no slouch when it comes to environmental awareness and concerns. After replacing my auto's antifreeze mixture, I had nearly two gallons (eight litres) that I didn't know what to do with. So I stored it in the original anti-freeze gallon jugs and forgot about them. After ...


4

You don’t want one row of panels to place the next row in shade. You need to make a balanced choice about panel spacing... too close and you lose useful solar energy... too far and you have too much darn lawn to mow...


3

Jon, First of all, I want to make a couple of points, A home owner can do any wiring or electrical on his own home so long as he is not actually tying it into the power grid and he does it up to code. Most of the codes are common sense so it is really easy if you step back and use your head. There is no reason to be scared, a system like you are talking ...


3

For me with a solar system in New Zealand, we've found the following quite effective: we've got a solar tank with 2 electrical elements in it, one at the bottom of the tank, plus another one about a third of the way down from the top. We run the bottom element overnight intermittently during the winter months when the whole tank is cool, the forecast is ...


3

The short answer is no. You might be able to produce a curve that will reflect an arc (spanning the days extent from east to west) all day on a given day without moving it, but only a small portion of such a mirror will be going into your window at a given time, wasting the rest of its arc. Further, (as the season changes) your north-south alignment has to ...


3

There's nothing electrically wrong with that proposal*, and it certainly is low cost - the plugs will be about $10 a pair. Wether extension-cord plugs are allowed in permanent wiring is a question for the local inspector, my guess would be no. Would I do it? Never. The branch circuits will run through places that make inline connections rather difficult, ...


3

Simply put a box and splices in the middle of the feeder Here's the rub -- transfer for a generator works differently than transfer for a hybrid solar setup (which is what you're probably envisioning -- forsaking grid-tie capability is simply not worth it unless you take the whole house off-grid). With a generator, the transfer means is essentially a big ...


3

It's easier to teach a violinist the bongoes than the other way 'round. You should be shopping for an A/C unit with "soft start". This is one of the reasons for these units to exist - ability to start off inverters, generators etc. They use an inverter drive to run the compressor motor. They are also able to run the motor at different speeds to suit ...


3

It is not that the compressor motor is inductive, but that, at startup, it draws far more current than while running. This is a characteristic of most electric motors, but is exacerbated that until it is pinning, having a large moment of inertia, the compressor is pushing against the "spring" of uncompressed vapor. The locked rotor current draw might be five ...


3

This is a 125A panel From the labeling on your panel, in particular the note about field upgrading 100A mains to 125A by replacing the main breaker and the meter-to-main-breaker wire jumpers, we can tell that this panel has 125A busbars in it, since UL wouldn't have permitted the manufacturer to provide such an upgrade as an option otherwise. The fact that ...


2

That does seem a little bit low but not crazy. I have a 3.3 kW DC array on my roof and during the peak times of the day I can get 2.7 kW AC after the inverter, or about 80% efficiency. I live in Northern CA though, where you can have cool and sunny days in the summer. Since you are in the US, one thing you should check out is the PVWatts calculator. This ...


2

If the hot water is hooked up to your faucets, then hot water should eventually come out regardless of the re-circulation stuff. That is, unless the check valve is the wrong way or the pump isn't letting water flow. Then you would just get cold water. EDIT I see from your comment that the system was previously working and no work has been done. The check ...


2

I don't know about "Crazy" but there are a few issues you should consider: Cost This is obviously going to vary a lot depending on where you live and how big the yard is, but you're probably talking about tens or hundreds of thousands of dollars to cover a yard. Power Usage What are you going to do with all that power? Many electric companies in the US ...


2

Heating a swimming pool is pretty much an ideal application for solar water heating. Relatively small delta-t requirements in mild weather means you can get high output from low cost solar collectors, and you can make use of 100% of the output. Payoff times for solar heating relative to equivalent natural gas heating can be as short as two years. You need to ...


2

I am assuming that you have 220V going to the barn? As far as wire size, industry standards say to aim for 1 - 2% voltage drop, but running 5000W, 200ft on #8 wire @ 220V results in just under 3% voltage drop. This will probably work just fine but it would work a little better if you were to upgrade it to a #6 or a #4. It is just a matter of weighing the ...


2

PVC (plumbing) is not rated for sunlight exposure and needs to be painted or otherwise shielded from sunlight. PVC (electrical) is not rated for plumbing/pressure use, but is UV resistant. So, if you have unprotected PVC pipe in the sun, expect more problems. And paint it, though already-damaged sections may still fail after painting due to existing damage....


2

You can want whatever you want to want, but that won't make it practical or efficient or cost-efficent (which comes back to practical.) There are at least 2 things that might be called a "solar tube" that come immediately to mind, and they are quite dissimilar. One is an "evacuated tube solar collector" and other other is a tubular skylight. I rather ...


2

That setup is terrible at so many levels, but fixable on all of them. First it's illegal under NEC because you won't find any plugs/sockets listed for use with solid wire. Plug manufacturers will never support solid wire, since cords need to flex repeatedly and solid wire can't. If the movable jumper had been done with proper cordage, then okay. ...


2

As the commentators have suggested, you probably could, but it would not be worth it. The big issue is that the solar panel generates DC electricity whereas your home outlets (and the power grid at large) are AC electricity. 10 watts is not a lot of power. Most home circuits provide 15 or 20 amps at around 120 volts, that equates to 1800 to 2400 watts. Keep ...


2

You certainly don't want to install the solar panels before redoing the roof. Outside of that obvious point, I don't think it matters much. In Theory, having the panel supports installed as part of the process of redoing the roofing could make things simpler and better sealed, but in practice there are very few, if any, teams trained to coordinate these ...


2

This isn't one of those games where the goal is to use only this bag of parts, right? Charge the battery with the solar panel Simply connecting a solar panel to a battery will not do what you want. It will overcharge and wreck the battery. You need a charge controller between panel and battery. This is a keystone product that will make or break your ...


2

Any dark colored mass would become a passive solar heater for when the sun goes away and the room begins to cool. The mass could be as simple as concrete blocks, tiles or as costly as eutectic tube solutions. Years ago,I was interested in solar systems (I was years ahead in my imagination and thinking), and these were common ideas that were studied and ...


2

You've ignored two major factors: Batteries don't live forever, and require maintenance as well as periodic replacement - more so if they are abused (typical when people save money on batteries and then over-discharge them.) This is one reason that "grid-tied" solar is far more common where the grid is available - it eliminates the battery storage and its ...


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