Working Thread for Solar Beginner Post/FAQ

Re: Where to Start: RV and Solar Power

For many of your loads, you have the choice of solar PV electric or alternative power sources (the biggest choice is probably the fridge on electric or propane power)...

If you live there 9 months or more of the year--then usually the choice is to pick an Energy Star fridge (even frostless in-door water, etc.) is a good one (around 400-800 kWhrs per year)... Propane, over the long term is probably a more expensive solution (cost of fuel, smaller/more expensive propane fridge, etc.).

ENERGY STAR government's home page

Off-Grid power, at least for planning purposes (assuming costs are spread over 20 years or so) still will cost you around $1-$2.00+ per kWhr. So--that "low power" fridge/freezer still will cost you between $400-$1,600 a year).

Note that small refrigerators are seldom energy efficient. A 2 cuft "bar fridge" may use 250 kWhrs per year. A 18-20 cuft fridge/freezer will use around 400-500 cuft per year. 2x the power for 10x the storage.

Looking at a fridge designed for off-grid use (solar or propane) are usually very expensive and have few "features" (not frost free, smaller than a standard fridge, etc.). Can be difficult to get service.

There are alternatives for many of the "power hungry" appliances out there... One of the neatest solutions is to take a chest freezer and change the thermostat over to one that will work in the "fridge" temperature range... Can get down to 0.25 kWhrs per day (instead of 1-2 kWhrs per day).

Chest freezer as a chest refrigerator
micro freezer

Solar Thermal can be a nice source for space heating and hot water... And usually is "cheaper" per kWhr/BTU vs Solar PV Electric. Also, Solar Thermal lends itself very well to do it yourself projects. Note, these are plumbing projects and have their own issues (leaks, pump failures, installation issues trapping air, anti-freeze, storage, heat exchangers, etc.):

Solar Shed and other Solar Thermal Links

A good place to start reading is Home Power Magazine... They have a free past issue online--and have a lot of articles you can read for free. I don't always agree with them and their reviews--but they are a fun and enlightening read:

Home Power Mag

You have not asked yet about wind power... At this point, I would suggest you forget installing a wind turbine until you have everything else up and running. Wind may seem cheap, but it is expensive to maintain and few turbines out there will last very long or generate very much power. I can add links--but won't unless you ask... Sort of feels like beating a dead horse (and I am not a pro-wind guy anyway--so it may look like I am being negative).

In the end, measure / quantify the power usage of every thing you will be feeding energy, work out its cost vs your needs, then plan the power system required to support it.

-Bill

Re: SUN-A-205-fa2 OR Evergreen ES-A-Series 205 Watt A

UL is probably the original Nationally Recognized Testing Laboratory.

Underwriters Laboratories (UL) was created for use by Insurance Companies to increase and document the safety of various products (starting with fire safety).

Testing is performed on "first articles" and ongoing manufacturing line inspection (built to specifications) and traceability (such as tags from fuse mfg. being installed inside power supply, insulation is from flame retardant plastic made to spec. in outside company, etc.).

Wiki History of UL

Originally, in the US, UL was the only safety organization that was called out in various local and state laws via building codes and NEC (National Electric Code). Typically enforced by fire departments and building inspectors--if there was not a "UL" mark, they could demand that the device/product/part be removed from service (no UL on coffee pot, unplug it or shutdown the business) or deny occupancy permits.

Also, insurance companies can deny coverage on claims if it is found that non-listed/recognized components where the cause of a fire, injury, death, etc.

In court, it is generally the basis for a defense that the entity being sued took due diligence that the maker/user took appropriate care in selling/using the product.

Note that NRTL's are (or should be) certified (competent) to test classes of products... For example a lab certified to test toys cannot test circuit breakers.

Some countries use UL/NRTL/local labs as a way to enforce trade laws (can't get in through customs without appropriate mark). There are many companies out there that are NRTL's--typical in the US include UL, CSA, ETL, TUV (several different companies), etc.

In the USA (and some countries) UL was the only approved lab (required by customs on imports).

In the last couple decades, there have been treaties (?) creating the concept of NRTL (Nationally Recognized Testing Laboratories). Each country would declare which labs where NRTL in relationship to their laws and codes (and remove, for example, "UL" from their codes/laws and use NRTL). This allowed other labs (domestic and foriegn) to perform safety certification and inspections (for internal use and export).

NRTL's are documenting the safety of various items. They are not guaranteeing fitness for any particular use or even that the product may perform the way the vendor says it does (although, there are new services that can document/verify the performance of "things" too--outside of the normal function of a NRTL).

What does this mean for you... In the US and Canada--if your project involves local building/fire inspectors, insurance liability coverage, or the possibility of using/operating the device can cause lawsuits (damage, injury, death)--then you are pretty much forced to use NRTL Listed/recognized components.

If this is for "other use" (personal use, use in an out building, not connected to the Utility Grid, etc.)--NRTL marking is not required--but can frequently still be a positive point (i.e., worth paying extra money for) to indicate that the vendor took basic steps to follow industry standards for the safety of a product.

This is different than the "CE" mark... While the "CE" mark implies certain safety, regulatory, and even documenting that the unit may meet functional requirements--This does not meet any "Safety" requirements in the US. The CE mark is self documented and certified by a declaration of the manufacturer. And does not require the validation of any outside vendor (may be some legal liability).

For an example of what can happen if a set of solar panels does not meet NRTL requirements see this thread:

Panel Fire Question

The long answer to a short question. :roll:

-Bill

Re: Working Thread for Solar Beginner Post/FAQ

Any suggested links to a Basic Electricity 101 for beginners? One I found that may be of interest is:

Electricity for Boaters - BoatSafe.com

-Bill

Re: Working Thread for Solar Beginner Post/FAQ

Add another very good Battery FAQ that is often recommended here (latest via Tony/Icarus). [I will add the three battery faqs here for one stop reading. -BB 4.7.2013]

https://www.solar-electric.com/learning-center/deep-cycle-battery-faq.html/
http://www.batteryfaq.org/
http://batteryuniversity.com/

-Bill

PS: Another interesting Battery FAQ with "gassing voltages" and how to charge Sealed Lead Acid Batteries first posted by mike90045 and Solar Guppy:

www.powerstream.com/SLA.htm

In this next link, is an older bulletin from Rolls (you have to click on this link to see the attachment) on how best to recharge deep cycle batteries. And here is the (text version) of the document. (thank you member "Volvo Farmer")

Re: Working Thread for Solar Beginner Post/FAQ

Trying to make this thread a jumping off place to further information (links, data, etc.).

Following up on Russ' Energy Star Suggestion:

www.energystar.gov
Energy Star Hot Water Heaters

Links to a couple of manufacturers from Solar Guppy (see above links for more):
No longer sold after 2016 -- GE Heat Pump Water Heater
Ruud Heat Pump Water Heater

For a quick discussion about heat pump based hot water heaters, see this thread (starting at post #12):

Guidance for Grid-Tie

Heat Pump based hot water heaters are probably a great idea for those in warmer climates (especially if using electric power or oil for heating).

If you are in a cooler climate (below ~55-45F area where heater will be installed)--check out the details to ensure it makes sense where you live--and I may very well be overly pessimistic on my suggestions--others disagree with me.

-Bill

Re: Working Thread for Solar Beginner Post/FAQ

Eric/Westbranch posted a link to a 1922 battery repair manual. A very interesting read and look back almost 90 years at technology and mass production (near the end are some factory photographs).

Antique battery info (1922) (thread)

And here is the direct link to the table of contents:

THE AUTOMOBILE STORAGE BATTERY ITS CARE AND REPAIR

Despite the title, also includes information on storage batteries too (Farm Lighting Batteries).

-Bill