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Advice needed on CA new construction system

Posted by redheadeddaughter (My Page) on
Wed, Feb 12, 14 at 14:05

Hello, We are building a 4600 sf home (2x6 construction, good windows but lots of them, crawl space foundation) on 2 levels with an unfinished attic (no basement) in central/northern california. The summers get quite hot (105-115 is fairly common). We won't have access to NG, so propane is the "default" way to heat our home (and range, etc.), and we are on 8 acres with a decent amount of flat for trenching if needed.

We'd love some ideas about what is commonly used in California these days, and what size system we should expect to see. The GC estimates have been all over the place! I've done some research into geothermal and hope to get some bids this spring in the hopes the prices have come down around here a bit. Any traditional ideas would be great too. We are on a budget, but it is somewhat flexible at this stage. Mostly just hoping someone with California experience recently could chime in.

Thanks!


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RE: Advice needed on CA new construction system

Size of each floor.

Prefer 2 separate systems. If not then one system with zoning controls.

The preferred system in Calif depending on location is nat gas furnace with AC condenser.

What is your electric rate? Any idea what propane is selling for in your location?

Geothermal is worth considering depending on your budget and type of acreage, ie non rocky. You might also look at Carrier's relatively new Greenspeed heat pump system. If going propane furnace, then definitely a high eff 95%+ model with staged heat and var speed blower.

What are typical average winter temps?

Post back.

IMO


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RE: Advice needed on CA new construction system

Thanks for responding tigerdunes!
Each floor about 2000.

No access to NG unfortunately. Very expensive electricity. It varies each month depending on the tier hit. I'll have to look at my last bill. I wish I could go all solar!

8 acres but somewhat expansive soil.

Average winter temps between 40-60 but as low as 20 in the evenings occasionally. Cold to me as I'm originally from Southern California, but no where near the winter temps of say, Wisconsin. ;)

My fear is that the cost of propane will go up over the next couple of years dramatically. I keep hearing there will be shortages. All rumor I'm sure, but still it has me looking at other options.

Does geothermal require alot of electricity to run the system? With such high AC bills in the summer I thought it might help, but maybe not.


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RE: Advice needed on CA new construction system

Scared of propane

Best advice is contact a reputable geothermal dealer. Let him look at your property and house plans. Get a budgetary number on project.

Then you will know where you stand and whether to proceed or eliminate him and drop back to a more traditional system.

I don't know alot about solar but you should do some research on the possibility.

Propane is just scary.

IMO


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RE: Advice needed on CA new construction system

Contact a Carrier Factory Authorized dealer and get a quote on the Greenspeed heat pump. It will be about a third of the price of geothermal after tax credits and it will perform very well in your mild winters.


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RE: Advice needed on CA new construction system

Thanks tiger dunes, I will get a quote for geothermal. Maybe solar too, since we have room and plenty of sun!

When I first read the "scared of propane" comment, I was sure you were making fun of me. ;) But now I think you honestly believe it's a bad idea. I'm curious is this because of your thoughts on the price of propane or another safety reason for use as a heating source?


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RE: Advice needed on CA new construction system

Where exactly is your new home? (Bakersfield, Fresno, Modesto, Sacramento..........?) Electric rates vary sigificantly throughout the state depending on utility. Geothermal will cost you an arm and a leg and your firstborn! Get an accurate payback comparison of geothermal vs electric (heatpump).


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RE: Advice needed on CA new construction system

Redhead

No, I am scared of propane because of pricing.

I do think you need a clear understanding of propane prices and your electric rates.

Look at geothermal first, Carrier Greenspeed second, and conventional HP third.

Can't really advise on solar, way above my pay grade. Worth further investigation though.

IMO


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RE: Advice needed on CA new construction system

By all means check with some renewable energy contractors in your area. Wind, photovoltaic and thermal solar are all good if the tax benefits in CA are generous.


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RE: Advice needed on CA new construction system

If you're a PG+E customer like I am, you have my condolences for having to deal with an all-electric house. I'm near the coast and have natural gas so the damage I suffer from their electricity prices is limited

I'd probably go with air-source heat pumps and spend the difference between that and geothermal (which will be substantial) on solar cells for the roof (assuming your house has the right orientation). I think you'll get a faster payback that way. Plus, the solar cells will shield some portion of the roof from direct sunlight, that'll keep the attic cooler in the summertime.

Propane scares me too but for a different reason - it's heavier than air and so leaks "puddle" on the floor rather than dissipate up into the air as lighter than air nat gas does. Leaks too frequently lead to explosions, much more so than a nat gas leak. If it were me, I'd probably keep it all electric in the kitchen and use the new heat pump type electric water heaters. If I were building a house with propane water heating, I'd put the heater in a outside-opening closet/nook with plenty of ventilation.

Good luck on your project and your new house!


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RE: Advice needed on CA new construction system

With that much property, the photovoltaic does not have to go on the house. It will be more efficient nearer the ground where the orientation can be adjusted to seasonal sun angle changes manually. Put thernal on the roof, maybe. Heat pump water heater with more PV might make more sense since there are fewer moving parts, but I understand that guyser pumps are an option.


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RE: Advice needed on CA new construction system

The thing about propane is you want to buy enough tank to hold you through the winter months so your buys are at a lower price. Having the propane company put a smaller (they provide the tank so they decide) tank puts you in a buy situation every 30-45 days.

As far as leaks go, get it done right and you are fine with gas. There are combustible gas detectors you can buy.


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RE: Advice needed on CA new construction system

Also, you are going to have to get a Title 24 done on the building. That will help these discussions a great deal.


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RE: Advice needed on CA new construction system

"...where the orientation can be adjusted to seasonal sun angle changes manually"

Ionized, I know a number of people with PV cell installations, no one does this. Also, roof installation is typically cheaper. The solar collectors for water IS a good idea, though.

Jackfre, a friend's Sierra ski house exploded when he entered after a Friday night drive up from the Bay Area and flipped on a light. Fortunately, he wasn't killed though he was pretty badly shaken up. The structure he ultimately rebuilt was all electric, needless to say.

Not just because of this incident, I wouldn't own or build a house that used propane. Even if doing so wound up being an expensive decision. Call it personal preference.


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RE: Advice needed on CA new construction system

Snidely, it is true that orienting the panels has less advantage as panel prices have gone down. Back when prices were higher, it was was worth paying for a system that changed the orientation during the course of a day and seasonally. Even seasonal orientation changes would be difficult on a roof, but on the ground, with a manual system, it is pretty simple.

Do you know anyone that has other than roof-top installation? I know that dominates, but our population is so urban that there are relatively few people with a lot of property to spare anymore.

There is serious discussion about whether solar thermal is worth it anymore for potable water. Photovoltaic with heat pump water heaters may pay off more. The trouble with solar thermal is that there are so many kinds of systems and every installation is so different, there are no economies of scale and installation is time-consuming. With PV/HPWH, installation is more like turn-key using relatively generic equipment.


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RE: Advice needed on CA new construction system

You've repeated the same comment, ionized, to which I'll respond (again) that I haven't known anyone who did what you've suggested or who had the tracking hardware.

Are you sharing your experience or just speculating? It's like Ron Popeil used to say about his kitchen gadgets, those I know with solar panels set it and forget it, ignoring them (other than monitoring output) once installed and operating.

I live in an area with suburban lots of varying sizes. I know one person with ground mounted panels, but others with enough space have tended to put the panels on their roofs. I think they're safer there and houses tend to be away from tree shade.

I'll end my comments here. I'm a homeowner sharing observations, nothing more. I'm not in the industry.


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RE: Advice needed on CA new construction system

You both may find some interesting info in the recreational forums (RV) - those guys routinely use photo voltaic cells either on the roof or on the ground.

Not only tracking the sun is of interest, but heck they change the orientation of their "array: each time they park.


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RE: Advice needed on CA new construction system

Hi salti,

I'm not an RV type but in thinking about it, the orientation would change every time they make a right or left turn too! Not sure why someone would want to mess with solar cells in an RV, it would be hard to get enough surface area to produce a meaningful amount of power.


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RE: Advice needed on CA new construction system

The thing about tracking hardware is that it is so expensive that for the say, 15% or so reduction you get due to sun angle you can buy enough extra panels to offset the loss, assuming you have the space. CA new title 24 states that on a new building you must provide an unobstructed roof area of 250 sq ft(no vents, chimneys, or roof penetrations). Those panels must be at least 3'below the peak to provide access for the fire dept.

It pains me to say it but solar thermal is about dead in the current American market. I was in the solar and alternative energy business in CA back in the late 70's-early 80's and did hundreds of hot water and other types of solar systems. They work great, but a dhw system today is around $10,000. That money is much better spent on a PV system today. Much better return on that investment.

Ground mount systems are fairly common up here in the foothills. My house is shaded by a Sequoia and a few 4' dia Black Walnuts. My only PV option will be ground mount out in the side yard or a new garage roof, I suppose, but then again I spent the garage on the house re-model;). I've seen several up here where they put the array up on a 15' or so tall post. There are, finally, initiatives underway now to establish better specification guidelines for DC power.

Snidely, I think you and I would get along great in person, but boy, we sure don't agree on much here. That is in no way a critical statement, quiet the opposite in fact. I'm a fitter/welder in an early life and worked on gas lines from 1/4"-36". I am very comfortable with it, but I understand the process of pipe design and installation. I do think that as we have codes that require smoke detectors that every home should also have CO detectors and, if supplied with gas, have a combustible gas detector. I am surprised that the insurance industry hasn't pulled that off yet. I guess not enough houses/people have been lost that way. Anyway, looking forward to meeting you on the next post;)


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Agree on all comments Jackfre. I didn't know the solar hot water industry was waning. I noticed a fair number of systems on houses during my most recent trip to Hawaii (where, as you may know, the electricity is very expensive, it mostly comes from power plants using fuel oil as the energy source).

I'd noted previously your having mentioned the Sierra foothills as your local. I guess my Bay Area-centric thinking made me think you were in the east of Sacramento toward Tahoe area. With a Sequoia tree, are you farther south, like in the Yosemite to Kings Canyon stretch?


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RE: Advice needed on CA new construction system

snidely,

You seemingly didn't do any reading about RV usage of solar panels. As I said, I am not an RVer, but I do read their forums because of their EXTENSIVE use of portable generators, solar power, and batteries.

Lots of space on their roofs and also many deploy arrays. I never suggested that their use of solar arrays would be limited to driving down the road.

Indeed some of the pressure to make use of solar arrays is to avoid the usage of (noisy) portable generators while in close proximity to other campers or while in National Parks which impose stringent restrictions on noise pollution.

Try google before dismissing their efforts to control their arrays. Just a thought. May be nothing to it.

This post was edited by saltidawg on Sat, Feb 15, 14 at 17:56


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RE: Advice needed on CA new construction system

salti,

Other than your comment, I didn't think this conversation had anything to do with RVs, sorry if I misunderstood or seemed dismissive. I'm not a camper/hiker/hunter/RVer.

Ionized seemed pretty insistent about people reorienting their residential panels through the course of the day. Maybe my mild sarcasm in a subsequent comment seemed to be intended in your direction. Not so.


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RE: Advice needed on CA new construction system

I'm not an RVer either - as previously said.

some of them do in fact use trackers for their on-roof or on-ground solar arrays. GOOGLE: RV solar array tracking

or more on point, GOOGLE residential solar array tracking

I have a feeling I did not help... sorry to all.


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RE: Advice needed on CA new construction system

“Ionized seemed pretty insistent about people reorienting their residential panels through the course of the day.”

No, I wrote “seasonal”, not hourly. If you don’t understand the difference between seasonal and “through the course of the day”, I can see why you missed my point entirely. There is no way that I would suggest, in this day and age that an expensive, automatic, mechanically complex panel orienting system would be economic.

My main point was that on an 8-acre lot, there many be much better places to put a PV array other than on a poorly-oriented roof. Unfortunately, people that have only seen panels on roofs, may not know that there are other options.

Seasonal adjustments in panel angle to meet the sun’s azimuth angle more closely are relatively simple. In temperate climates will gain you about 5% if done twice a year. Is that worth it given how inexpensive PV panels have become? It depends on how hands-on the owner is, and how much more it costs to build simple, adjustable mounts.


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RE: Advice needed on CA new construction system

"Agree on all comments Jackfre. I didn't know the solar hot water industry was waning. I noticed a fair number of systems on houses during my most recent trip to Hawaii (where, as you may know, the electricity is very expensive, it mostly comes from power plants using fuel oil as the energy source).
I'd noted previously your having mentioned the Sierra foothills as your local. I guess my Bay Area-centric thinking made me think you were in the east of Sacramento toward Tahoe area. With a Sequoia tree, are you farther south, like in the Yosemite to Kings Canyon stretch?"

Actually we are in Nevada City. Our place shows on CA maps from the 1860's and I am told was the old stagecoach station. I have been unable to verify that at the Historical Society, but continue to search as time allows. The earliest date I have found on newspapers glued to the interior sheathing is 1879. Apparently, while not prolific, there is the odd Sequoia this far N.


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