Tiny House Solar

Yes but research neutral bonding ground on inverters, many of the consumer level ones not designed for hard wiring burn up when the service panel bonds the neutral to ground.

Looks like you are correct about the transfer switch being setup for using a PROWatt for hard wiring.

The reviews on the TrueCharge 2 seem mixed.

I would just suggest considering the cost of the PROWatt, TrueCharge 2, and transfer switch against the cost of an inverter charger built for this aplication. Keep your eyes out on Craigslist. I know it is of little help to you in Bakersfield but a quick search near me turned this Outback VFX 2812-M for just over $1K.

I started with a small system -- and I grew mine. So it IS doable, but you have to be careful with what components you buy.

My initial system was 12v. I had:

4x 230w panels
8 6v GC2s wired in series/parallel (4 parallel strings! YEEK!)
Cheapy HF 2000/4000 12v MSW inverter
PowerMAX 100A 12v smart charger
Classic 150 Charge controller.

Knowing that i planned to move to 24 or 48V later, I bought a charge controller that could handle my expected system size down the road. To minimize the amount of wasted money, I bought a cheap HF inverter to tide me over until I could buy a good PSW inverter.

Later, I added more paners (5 more) and 8 more batteries and an Outback VFX3648 inverter. The only tech I had to get rid of was the 12V inverter and 12v charger.

Since I still maintain a small 12v system to power some 12v stuff and keep the generator battery full, I am still using the charger -- so the only thing that was "wasted" was the cheapy HF inverter, which only cost $129 on sale.

SO, with careful thought and research of where you want to wind up, you CAN minimize the wasted money -- but you have to have done all your planning homework first. One place that I didn't plan as well as I should have was in my batteries. I should have started with 8 L-16s and then grew them to 16 L-16s rather than GC2s. Having more than one string of batteries is not optimal, but I feel that 2 parallel strings is the reasonable maximum. I could use more battery capacity than I have now, but that would also mean adding more panels so that I could charge them properly.

As it is, we reach float almost every day, and only draw the batteries down to about 76% SOC overnight. I'd rather see that number in the upper 80s (hence the desire for more storage, and therefore more panels), but I can live with it -- during the day we have enough power to run our fridge and freezer, a swamp cooler and sometimes a window AC if we get to float early enough. At night, we have the fridge and freezer on timers to shut them off from 11pm to 6am, so my night draw is usually around 200W constant all night -- I could make that less by shutting down the media server and wifi, but we've decided that we want to leave that on and we're OK with the power it uses.

All of our lighting is LED except for the CFL "bug light" on the porch. I haven't found (or really looked hard) for an LED bug light. However, since the porch light isn't on for very long, the fact that it uses 20w instead of 10 is really not that big of a deal. The porch light is usually on for only a few minutes at a time.

So, PLAN PLAN PLAN PLAN PLAN. Use a Kill-A-Watt. Design your "final" system -- where you want to be for the next 5-10 years. Then, if you can't afford to buy all that at once, very carefully examine your plan to see where you can cut costs, but at the same time, minimize how much tech/money you will have to "throw away" later.

The process you are going through is similar to many first starting out, including myself. It is fun to get some equipment and feel the thrill of having a working system. But generally results in geting the wrong equipment for your ultimate needs and learning through trial and error what you actually need.

The loads listed will likely require a system several times larger than you are planing.

Please explain the shore power availability vs need for solar. It sounds like generally shore power will be available where you plan to park your Tiny House but perhaps you want solar for the odd occasion it is not available and perhaps for the fun and coolness factor of having solar?

Perhaps a small solar system to run some lights, computer, and a few small loads on occasion would be better. Then invest in a good inverter generator like an EU2000i which can run your larger loads several hours a day with good fuel economy and little noise.

meestro wrote: »

- MacBook Air (45W to charge every 2-3 days)

Understand the difference between a Watt and a watt hour. So it draws 45W, but for how long?. Mulitply the two to get watt hours. Then you have an energy budget, total Wh needed per day. THEN you can start desiging.

You also need to get a sense of the actual draw. It might say 45W on the adapter, but thats its max rating. Measuring it (or researhing) will yeild a more accurate result. Imagine hypothetically it only draws half that in practice. You just cut the cost of your solar system in half?

For example: from practice i know a certain 30W adapter uses about 10W and about 20W when its both powering the device and charging it at the same time.

there have been comments about which is more efficient use of PV power, to leave the PC plugged in 24/7 or as needed...

No definitive answers, if you were to test the theorem....?

meestro wrote: »

I'm getting an average of 61-62w operating power from the refrigerator. I see .28kwh as well.

To reiterate, in this game units are everything. 62W is the motor running power, not the day average? And 0.28kWh is 0.28kWh/d?

What you need for appliance testing is the kWh PER DAY. Thats the only useful metric to you. Set a stopwatch (or zero the power meter) and run the fridge for at least a day (while the fridge environment is at a typcial ambient). Divide the total kWhs used, by the total number of days eg 1200Wh / 1.08 days. THEN you have the figure you need for your energy budget. You can also safely use this figure to meaningfully compare fridges.

BTW if 0.28kWh is per 24.0 hours, then if so thats a nice efficinet fridge. Hang on to it!