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6

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 ...


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

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 ...


3

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 ...


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 ...


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

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 ...


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

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 ...


2

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 ...


1

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 ...


1

Better idea: get panels with their own micro-inverters. Then you can add more panels at will in the future. Bonus: micro-inverters are more efficient than a central inverter and will last longer.


1

The longer and less direct the run,the more light you will lose to absorption. And of course the split would mean you lose light in the original location. If you really want to do this anyway, I'd consider real optics -- half-silvered mirror, focusing lenses, front-surface mirror at far end -- but cost would be high. A second sun-tube/skylight seems a ...


1

What you are hearing about are called "micro-inverters". Instead of one large inverter, you have separate, small inverters, one on each panel. I believe you can get them both sepatate and already integrated into panels. This would require rewiring your PV system, removing the old inverter and installing micros at each panel. as you say, probably not cost ...


1

With grid-tie being illegal, there's really not a way to do what you have diagrammed, as far as I know, and I spent several years working towards a large and complex off-grid system before local conditions changed and it became practical for me to grid-connect. In particular, the "draw from solar, supplement from grid" (or questions 2 & 4) part does not ...


1

I think there are two levels of Battery backup here, First you can do a full move into Solar. in which case you would need a LOT of changes to your current setup (energy efficient devices, LED Light Bulbs, Solar Geyser, LED PC Screens, LED TV, Alternatives to tumble-dryer, gas stove etc. ) I dont think its as easy as spending lots of money on a solar ...


1

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 ...


1

Are the PEX hoses black and is the sun side of the re-purposed aluminum plates black? If not you may want to consider changing this so as to increase the efficiency solar energy absorption.


1

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 ...


1

Pretend your panels are a water pump connected from a nearby pond (your roof) to a water tower (the grid). The grid is a large reservoir that can simultaneously take and provide electricity. This is because there are multiple sources and destinations for the electricity. If no one else was using electricity when you were providing it, your meter would ...



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