Solar Power Questions

[mwester]

Preface: I need advice regarding purchasing and implementing a small solar power solution.

 

I'm considering adding a set of solar panels here -- I have a small outbuilding with a metal roof oriented east-to-west, and am thinking of covering the south-facing side with a set of panels.  So, the first question is what others here who've done this sort of thing would recommend in terms of a supplier for panels?  A google search shows a plethora of panels, with every vendor claiming they have the best... I'll do the research of course, but I'm happy to start my research by asking you all!  (BTW, northern US in terms of geography -- not ideal for solar, but wind power is even worse here).

 

Second, I'll need an inverter -- and things to control the inverter and related components.  I hear they can interfere with the Insteon power-line signal (which is the last thing I need, since my Insteon performs so poorly already!).   Anyone willing to share experiences around this?  (The building in question is out of range for z-wave, so it'll have to be either over-the-power-line comms, or I'll have to pull a separate underground cable for data... which is ok, but not ideal.)

 

Finally, I'm not doing this for economic reasons - I doubt it'll ever pay off this far north.  But I'm interested in how the economics have played out for others.  Any comments on this?

 

Feel free to talk me out of this potential foolishness.

[Dr Pepper]

On Long Island electric is $0.22 a kwh and a leased solar arrangement is $0.16 kwh.  So if my electric bill is $300 a month on balance billing I could save about $120 a month "if" the leased system could supply all of my power.  Had them come in and do their survey and they can produce about a third of my electric needs if I removed a tree and the neighbors remove a tree and save about $40 a month.   Math did not make sense so we didnt bother as it would take a couple of years to break even on just the tree removal.  If we had a larger roof area that had better exposure we could have probably cut our bill almost in half so for many it makes a lot of sense.  My point to you is do you know how much power you need  (might be a lot less than a house unless its a workshop with lots of power equipment) so you can size it correctly and also verify you have enough roof area.

 

Look at Costco online for their packages.  You might find one you like and they stand behind what they sell and its easy to return it if it causes interference (set it up on the ground and do a trial run before putting holes in the roof of the building). 

 

Zwave should go about 300 feet open air (or even more).  If you mount a Zwave device on the outside of your house and another on the outside of your outbuilding you might make it.  I saw once where someone ran electric from their barn to a fence post and put an Zwave outlet and it cut the distance by another 50 feet which made all the difference in their situation they said.  I dont remember their total distance but it was pretty far I think.

 

NOTE:  I have two 100 watt panels on my shed that I use to keep two deep cycle marine batteries fully charged and also charge a lot of my 12V and 5V devices (cell phones, tablets etc) and I also can use them with an inverter to run my furnace, gas hot water heater with electric ignition, and a refrig for a short period of time in a blackout.  I really need to add a third panel and third battery when the money is there to get a reasonable run time.

[MikeD]

We have Hyundai panels with Enphase microinverters. Insteon uses power line communications similar to the Enphase microinverters. I read that Enphase communicates over the wiring at 144 kHz and Insteon at 131.65 kHz.

 

Reading through the Enphase Troubleshooting guide they suggest using ferrite toroids to eliminate interference between the two systems. Reference pages 22 & 23 of this document. http://www2.enphase.com/global/files/Enphase_Troubleshooting_Guide.pdf

 

Page 22 has a link to the suggested ferrite toroids. http://www.digikey.com/product-search/en?vendor=0&keywords=Epcos%20B64290L0%20082X087

 

I found information on this topic here. http://forum.universal-devices.com/topic/15084-enphase-m250-micro-inverters-and-insteon/?hl=enphase

 

We installed the suggested ferrites and our solar has been in operation for over a year with no ill effects to Insteon communications.

[larryllix]

Almost any supplier would be suitable as the solar panels are the cheapest part of the system now.

Most of the panels here run about $0.80 Canuck buck.

 

Things in the PV world have changed a lot over the years. My initial system cost me about $30K and will never pay off. Matter of fact, if RoI and all factors considered it would never pay the interest for the RoI lost.

Now you will find the PV panels to be the least cost in the system. My latest confirguration the mounting, wiring, aaccesories cost more than the panels. Tracking systems are a waste of money. Get more panels and forget the complex mechanisms.

 

I had an inverter fire a few years ago and it cost me $16K to replace with a better system with better technology.

 

You will find PV panels come in two different configurations. With 24v panels the MPP voltage comes at 30v and 36 volt. This is based on 0.5v/cell and 60 or 72 cells per panel. A 30v panel cannot charge battery systems without a non-standard configuration. I run a 48v battery bank and it takes 62 v to equalise the battery bank properly and with a few volts of loss in the wiring two 30v panels in series won't do it.

Batteries incurr another 40% loss of energy charging and discharging.

 

Snow is a factor. My panels are buried deep in snow during most of December to March. In this case a very steep angle is important to shed snow and harvest more in the low sun angle months.

 

Currently I run about 2500W of south facing (newer cheaper panels) and 1000W east facing (old panels) and 600W west facing. This is the result of attempting to replace my older system and nobody will pay you $0.05 per watt for them despite still being expensive units. The ended up being awnings for morning ans evening sun. This squares off the power curve each day. Occasionally the sun hits them all simultanously and I jump for joy, with the huge power peak.

 

The most lucrative method here is the micro-inverters under every panel. I horse ranch up the street has some 400 large panels and inverters on the roof and I have seen them all replaced twice now. Ouch! The Ontario government had an $0.83 per kWh gift, that these fell under. Nice.

 

Without batteries, the frustrating part is when the grid fails watching the sun shine and all that being absolutely useless while you can't even flush your toilets.

 

Although the challenge would be tempting, we would never go off-grid. Rule of thumb is you need a geneartor that you will require about 3-5 times per year. If you require it more, you need more system. If you need it less you overspent. Big lifestyle change and we don't want to do that.

 

..."Honey! The sun is shining! Quick do the washing!"

......"I'm leaving you for a less energy efficient man!"

[JayC]

check out Google Sunroof: https://www.google.com/get/sunroof#p=0

[Scottmichaelj]

check out Google Sunroof: https://www.google.com/get/sunroof#p=0

Well there goes that idea! LolNot that I thought Seattle would be a good place for solar panels! I get less than 1 hour of sunlight per sq ft of my roof.

 

[larryllix]

Just remember. it is not heat that prodices energy with these PV panles..it's light.

 

Look for "solar insolation maps" (no typos)

 

The northern midwest US and lower midwest Canada are about the best areas producing about double the energy the same panels with the same angles would in Ontario.

 

 

Most of the systems, without any governement kickbacks, or grants, will never even pay the interest incurred on the bank loan or against other loss of investment. It's a sad fact, but do the math, honestly.

 

Having said that, energy rates are changing dramatically here. With my set up now, I only use about $20-$30 worth of energy per spring-fall month, after the panels do their stuff and feedback credits, making my bills only about $150 per month after all the extras. Battery systems are the main economic loss.

 

We are not allowed TOU metering and the constant rate during sun times hurts us. They have recently kicked PV people with flat rates across the board for delivery and extras despite the government shooting their mouths off about clean nuclear electric, and carbon tacks in our back!. OUCH!

 

The interest lost at even 5% per annum, on the $45K spent so far, would be $187.50 per month. That is if I never paid back any principle on the money, I don't have. I would be sure that money would have netted more elesewhere. It's been fun, but a very expensive hobby.

[jtara92101]

Does anybody know anything about this? I'm not sure it's a real product yet - I think it is a completed Kickstarter:

 

https://www.plxdevices.com/Legion-Solar-s/123.htm

 

https://www.kickstarter.com/projects/plxdevices/legion-solar-a-better-way-to-energy-independence

 

I'm skeptical of the "just plug it in" claim. I understand that at least in San Diego, you need a permit. And I assume there is some utility-provided interface?

 

A friend up the street want to put in solar. Something like this (or what you can get at Costco) is attractive, since he does most of his own work on 2 apartment buildings and a house that make up a complex. There is lots of roof space! (Including  a garage). If the majority of the cost is installation, then Blue Shield will pay the bulk of the installation cost, LOL.

 

I only know about it because I have the same company's OBD2 dongle in my car. I like the product, and it works well with 3rd-party OBD2 iOS apps. They promised their own iOS app, and that had a Kickstarter, but that was due in January, and now it is end of May. As a software developer myself, I understand how that goes! I was pretty sure they were over-promising.

 

Oh. It looks from comments on Kickstarter that people have started to receive the products. There have been some problems with damage in shipment. At least it seems it's a real, shipping product.

[larryllix]

Does anybody know anything about this? I'm not sure it's a real product yet - I think it is a completed Kickstarter:

 

https://www.plxdevices.com/Legion-Solar-s/123.htm

 

https://www.kickstarter.com/projects/plxdevices/legion-solar-a-better-way-to-energy-independence

 

I'm skeptical of the "just plug it in" claim. I understand that at least in San Diego, you need a permit. And I assume there is some utility-provided interface?

 

A friend up the street want to put in solar. Something like this (or what you can get at Costco) is attractive, since he does most of his own work on 2 apartment buildings and a house that make up a complex. There is lots of roof space! (Including  a garage). If the majority of the cost is installation, then Blue Shield will pay the bulk of the installation cost, LOL.

 

I only know about it because I have the same company's OBD2 dongle in my car. I like the product, and it works well with 3rd-party OBD2 iOS apps. They promised their own iOS app, and that had a Kickstarter, but that was due in January, and now it is end of May. As a software developer myself, I understand how that goes! I was pretty sure they were over-promising.

 

Oh. It looks from comments on Kickstarter that people have started to receive the products. There have been some problems with damage in shipment. At least it seems it's a real, shipping product.

I have seen many of these wild claims over the years but usually when they go for actual approvals by the authorities, things they know nothing about, like safety applied in a real grid system cause massive culture shock.

 

Most unsuspecting home owners would drop it and run once they find out a separate pipe with appropriate conductors (capacity derated due to more than three) must be run out to a safety disconnect lockout switch beside their electrical utility meter by an electricaian before tying this into their panel.

 

Linesmen don't like the possibility of backfeeds when a high voltage feed goes out and they have to dig it up or work on the transformer feeding it. Now this requires an approved lockout switch with lock and tagging provisions, approvals, huge rolls of Red Tape, and can cost more than the measly few bucks they thought brough them a gift from energy heaven.

 

Unregistered, if some linemen detects a backfeed from an undocumented source, heavy fines are usually coming. If somebody dies, or even gets shocked or burnt, the owner is going to jail, after paying the fines. Suddenly it backs up into the manufacturer and the president and maybe a few wanna-be engineers, pay heavier fines and/or spend jail time. YMMV