new to the solar thing so very simple questions

System

1. can you have the whole house on solar?
2. what is the cost of a system vs the savings?
3. can you mount them on clay tile roofs?
4. where is the best place to buy this suff from

Roderick

Re: new to the solar thing so very simple questions

paqman wrote:

1. can you have the whole house on solar?
2. what is the cost of a system vs the savings?

I'll make a start on your first two questions, and I'm sure the experts will chime in after the holiday. These questions are intimately related to each other, in my opinion.

It's absolutely possible to put the entire house on solar. Remote cabins do it all the time. If you have a house that is presently connected to the grid, it rarely pays to go completely off-grid from the *financial* sense. If you want security against power outages, or want to contribute to the environment, that's another matter.

From the financial sense, the best payback is from getting energy efficiency through insulation and efficient appliances. And I'd say second after that is going to solar water heating. Other solar heat is probably in there somewhere, but I don't know anything about it (I'm presently in Hawaii, heating is not an issue).

To go towards the goal of powering a whole house with solar, one needs to start thinking about shade and fans instead of A/C. On the other hand, to move towards saving money, one might put up a grid-tied solar array to only supply the most expensive fraction of electricity. For example, if you use 30 kWh a day, but pay a premium rate for the last 20 kWh, then you would try to size your photovoltaic system to supply that 20 kWh, and pay the electric company for the (hopefully cheap) first 10 kWh. This can be extremely cost effective if you're a big electricity user. And you'll never have to worry about batteries.

Okay, got to get back to the 4th of July preparations...

Mangas

I am not an engineer nor an expert on solar installations but I did a lot of planning and supervision on mine. Many people in my area have asked about what I did. I am passing along my own thought process, if it might help you.

I have an off grid solar energy plant which powers just about every application someone would use on the grid. To do so, I substituted some energy applications and balanced other technologies to equal grid capacity.

For example, I decided that central heating delivery (air handlers) and central A/C cooling (multiple stage compressors and air handlers), house water system, livestock water system, fire protection, lighting, security and appliances would be powered by solar. Hot water, central heating (furnaces) and cooking would run propane.

The cost of building a solar system to include what I decided to run on propane was either beyond my investment budget or judged to deliver only marginal performance. Everyone will have a different investment threshold. While mine was high it wasn't unlimited.

My opinion is to invest in the most effiicient, reliable and high quality technology/products available rather than trying to exact maxmium output (on paper) with the least investment. For example, they make many furnaces some bi-fuel some straight fuel. I chose more expensive 19 SEAR variable speed bi-fuel furnaces and A/C compressors rather than cheaper units because of their durability and power efficiency. The same applies to solar components. The experts on this board are well informed on which ones make the most sense for you. I've learned a lot from them already.

Also, alternative building systems help a great deal. In my case, I used RASTRA construction with very high R and fireproofing ratings. More expensive but recovers the initial investment very quickly.

As the previous poster suggested it's a matter of balance. If you are on the grid then, you have all the flexibility to "scale" your solar installation to how much you're willing to invest and essentially, net of the solar investment, reduce your energy costs. If not you'll have to make trade offs. No matter what you decide, my recommendation is to build 20% extra capacity into the system.

The incentives to invest in alternative technologies will only get better
in the future which will impact your investment outlay. For me, I built the system because the ranch is in permanent conservation bordering the national forest. This was the primary driver in my decision to use solar exclusively. Others will have different objectives.

Finally, while a 100% off grid system is able to power just about all of anyone's requiremments it's expensive in todays dollars. But, I also believe electrical grid power rates are going to increase very substantially over the next 10 years. My initial solar investment outlay should therefore be moderated.

What may not make financial sense to some people now may make a lot of sense 10 years from now.

Vic

Hi Mangas,

At the risk of hijacking this thread ... gotta say that your system seems very ROBUST !

Had not heard of RASTRA previously, but will look into it.

Have built a small cabin in the outback of NorCal, using traditional methods -- wood/stucco. Did this simply 'cause that was what the available builders were into. Having not done this before, felt this was about the only approach ... very difficult getting labor into this remote location.

This cabin is a starting point. There is a second loaction on another plot which needs a modest structure. Hopefully I can learn from the first cabin project and from others the way the first structure should have been built !

Solar PV is quite magical to me, as it simply sits aroung silently making substantial amounts of power, year after year, with almost no maintenance required. Running a generator will always be cheaper, but PV is magic to me.

Enjoy the fruits of your labor and investment. All the best, Vic

Mangas

Re: new to the solar thing so very simple questions

Thanks Vic.

I think you'll find RASTRA an excellent alternative for remote located projects. The R and fire proof ratings are excellent. I found it far simpler to build than frame construction. I put up a foot print over 4,500 sq ft. Visit the RASTRA website.

Let us know how it goes.

Scott

System2

Re: new to the solar thing so very simple questions

Where online and offline can I find a complete overview of a complete legal solar installation, where I can do a comparison study for a prospective install.
Also where can I find basic solar installation diagrams showing paralell vs series installation if that is even possible.

Windsun

Re: new to the solar thing so very simple questions

www.homepower.com

they have some sample articles you can download, at least 2 with complete system diagrams.

BB.

Re: new to the solar thing so very simple questions

"Legal" covers many issues... Legal Electrical, latest National Electric Code (NEC).

Connection to your Utility (Grid Tied Inverters)... State by state, and sometimes utility by utility (our utility requires building permits and insurance statement--homeowners was enough for mine). Different billing options (net metering 1 year is best, some states are month by month net metering, others pay you a few cents per kWhr over what you use). Some utilities do not allow.

Some places have made it very difficult to add solar panels on home or property, some states (California is one), have passed laws that say if the installation meets normal codes and does not look too bad--the local people have to allow it to be installed (with up to 20% special requirements dollars allowed).

I could not find it, but there is a book (online?) that a was written to help ensure that a solar installation meets the requirements and spirit of the electrical code (John Wiley? sp?)... I am sure somebody has the links.

-Bill

crewzer

Re: new to the solar thing so very simple questions

These may the "John Wiles" links to which Bill is referring:

"Working With your Inspector / Checklist": http://www.nmsu.edu/%7Etdi/pdf-resources/CC113.pdf
John Wiles "Portal": http://www.nmsu.edu/%7Etdi/Photovoltaics/Codes-Stds/Codes-Stds.html

HTH,
Jim / crewzer

BB.

Re: new to the solar thing so very simple questions

Yep, that is it.

Thanks Jim

-Bill

crewzer

Re: new to the solar thing so very simple questions

More info:

Offline: See the NFPA National Electrical Code in general, Section 690 in particular. The NEC is updated every three years; the latest version I have is 2005

Online: This one is handy, but it's starting to get old: http://www2.fsec.ucf.edu/en/education/cont_ed/pv_handbook/Inspector_NEC.pdf

Online: These may the "John Wiles" links to which Bill is referring:

"Working With your Inspector / Checklist": http://www.nmsu.edu/%7Etdi/pdf-resources/CC113.pdf
John Wiles "Portal": http://www.nmsu.edu/%7Etdi/Photovoltaics/Codes-Stds/Codes-Stds.html

Online Google search string: http://www.google.com/search?hl=en&as_qdr=all&q=NEC+%22photovoltaic+power+systems%22&btnG=Search&lr=lang_en

Schematics: Home Power magazine used to have a couple of "clickable" schematics available. Those schematics are a bit old, and I think the links have been removed.

HTH,
Jim / crewzer

P.S. Anybody else having a problem getting the "Edit" function to work? Most of my edit attempts end up with the little spinny-thingy just spinning away endlessly...

BB.

Re: new to the solar thing so very simple questions

Edits--couple days it work fine, next couple of days, it fails (even editing on the same post).

-Bill

niel

Re: new to the solar thing so very simple questions

i had trouble once when i went to edit and it did exactly that, just spun around in circles, which is the busy indicator for vista. jim, did you get vista? i'm sorry i did and i may go after xp pro soon if there's any of them left.
hmm, it worked on this try for my spelling error i had on sorry.

crewzer

Re: new to the solar thing so very simple questions

niel,

I'm still using Windoze Ex-Pee on my home PC, albeit with all of the latest updates and a couple of third-party anti-virus- and anti-pest programs in addition to Defender. I'm not planning to go anywhere near Vista for a while... I work for a major engineering and IT company, and our IT folks haven't approved Vista nor IE 7 for our office machines.

Regards,
Jim / crewzer

Attempt to edit

crewzer

Re: new to the solar thing so very simple questions

I made the edit above using the Edit screen's "Go advanced" button instead of the "Save" button.

niel

Re: new to the solar thing so very simple questions

never tried the go advanced as it works on save for me.
i'll bet they won't approve vista for a very long time as it is twice the size in its requirements with less than half the abilities of xp. in addition, it is very picky what goes on it as in my conflict with media player when i chose to put another player on here. it seems 2 can't be on here at the same time without troubles. i know i've said this all before, but i can't say it enough as this os sucks imho and is a step backwards and not forwards, not to mention the little annoying windows popping up asking if this action is ok all of the time. i do have to admit one thing, i haven't had a virus with it yet, but heck you can't get many programs to work well with it let alone a virus.

crewzer

Re: new to the solar thing so very simple questions

Also where can I find basic solar installation diagrams showing paralell vs series installation if that is even possible.

Dead Run,

The issue of “series vs. parallel” can get a bit complicated. Variables in systems with charge controllers and batteries include panel specs (Voc, Vmp, Isc, Imp), array size (Watts STC), nominal battery voltage (i.e., 12 V, 24 V, 48 V, battery type (AGM, gel, flooded-cell), type of controller (PWM, regular MPPT, DC-DC MPPT), environmental conditions (i.e., high and low ambient temperatures), and length of “home run” cables between the array and the controller.

While many systems are connected in similar styles, there’s no “standard” installation diagram that covers all of these points. The link below will take you to an old Home Power schematic for an off-grid solar energy system. It's probably more useful as a detailed block diagram, as many of the components have been superceded by improved technologies.

See: http://www.suncatchersolarhomes.com/ResidentialSolarProducts.htm

Can you tell us more about your plans?

Regards,
Jim / crewzer