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WindwardGamer
August 9th, 2007, 10:40 AM
Hello,
Am getting tempted by the rebate/tax credits and general appeal of solar water heating for our Kailua 4/3 home (2 adults, 3 kids). There is a long list of HECO approved contractors at the HECO website (http://www.heco.com/portal/site/heco/menuitem.508576f78baa14340b4c0610c510b1ca/?vgnextoid=15895e658e0fc010VgnVCM1000008119fea9RCR D&vgnextfmt=default), plus I get occasional offers in the mail. Too many choices... :confused: Has anyone done this recently? Do they all charge about the same price? Looking for quality and a good price, anyone have a recommendation? Did you get the advertised reductions in your electric bill (~$5-$10 per person per month)? Anything to watch out for, "gotchas" :eek: I should avoid?
Thanks in advance for any advice! :)
-Don

craigwatanabe
August 9th, 2007, 10:52 AM
Make sure the solar panels you buy have a really good warranty, like over five years. Working for the Gas Company when it was called PRI, we used to do Solar water heating work.

Generally you'll save approximately 50% on your energy bill by going solar. It typically took five years of savings for a solar water system to pay itself back from the initial cost of buying such a system.

The downside for some was that at five years the panels started leaking and the warranty had expired. So you have to replace the panels at your cost and there goes the accrued savings over those years of service. You basically broke even had you simply used a conventional electric water heater.

And while we're on the subject of electrical costs, forget the notion that you'll save energy by using your electrical appliances during non-peak hours. Unless you have a demand recorder attached to your electric meter and you have a provision in your HECO account to be discounted for use during those non-peak hours, you won't see any change in your electric bill no matter what time of the day you blow out those Kilowatts.

You'll save HECO some money by not taxing the power grid, but then if everybody cooked their turkeys at 11pm instead of 6pm (peak hour) then the same energy grid is taxed regardless but at a later time of the day.

If HECO tells you your energy costs can go down by running your appliances during non-peak hours, then call them up, request a demand recorder (a device that records usage in hourly, daily, weekly units) and to go on a billing program utilizing off-peak metering savings.

Pretender
August 9th, 2007, 04:22 PM
You should get multiple quotes, even if you pull the contractor's off of HECO's list. I would also look up their complaint record (if any) on the State DCCA website. My mom recently used Ponchos and their system is working fine. The previous system was in place for over 20 years, so you can get good service life out of a quality system.

Good luck.

oceanpacific
August 9th, 2007, 05:37 PM
Some firms only sell the components and sub-contract the entire installation. Choose someone who can service, not just sell, the system. I recommend David Hutchinson of APOLLO SOLAR. His components, design, and installation are top-notch. No short-cuts, but, you pay about the same.

Dave started at APOLLO as an installer in 1978 and took over when the original owner retired and moved to the mainland in the late '80s.

Where you live in Kailua will determine the "sizing" of your system (square footage of panel area to gallons of water tank capacity). I'm in Mililani with perfect orientation (direct south), so my 100 gallon tank only needed 48 sq. ft. (two 3' x 8' panels). If your orientation is not due south, their panels can be installed with the necessay tilt to optimize system efficiency.

My system has been in place since 1994 with zero problems.

Feel free to PM me for additional information.

chicodog
August 10th, 2007, 07:30 AM
We got our solar in 1980 from PRI and the only service we needed was to change the water pump and one of the heat sensors by the solar panel.

Nords
August 10th, 2007, 07:43 AM
Hello,
Am getting tempted by the rebate/tax credits and general appeal of solar water heating for our Kailua 4/3 home (2 adults, 3 kids). There is a long list of HECO approved contractors at the HECO website (http://www.heco.com/portal/site/heco/menuitem.508576f78baa14340b4c0610c510b1ca/?vgnextoid=15895e658e0fc010VgnVCM1000008119fea9RCR D&vgnextfmt=default), plus I get occasional offers in the mail. Too many choices... :confused: Has anyone done this recently? Do they all charge about the same price? Looking for quality and a good price, anyone have a recommendation? Did you get the advertised reductions in your electric bill (~$5-$10 per person per month)? Anything to watch out for, "gotchas" :eek: I should avoid?
Thanks in advance for any advice! :)
-Don
We have two 4'x8' water panels and 3000 watts of grid-tied photovoltaic panels on our Mililani south roof. We've had the PV running since early 2005 and the water since early 2006. The water panels are at the top of the 2nd story (http://i11.photobucket.com/albums/a191/Nords_Nords/Solar%20photovoltaic%20array%20expansion/Allpanels.jpg). Last month's electric bill was $18 but this month's will probably be lower.

You'll probably spend $3000-$4000 and get about $1500-$2500 back in tax credits. The payback will be at least $5-$10/month but the "good" news is that with three kids you'll probably save even more. 3-8 years is a typical payback time for a system that'll last at least 25 years.

I've learned a tremendous amount about solar contracting from Keith Cronin at Island Energy (http://www.islandenergy.net/). Although he no longer does water systems, he recommended John at Grand Solar. I've never had to use Grand but Keith and his crew are top-notch and active in the Hawaii Solar Energy Association. If contractors stumble then the network stops referring them. It's been a few months since I've talked to Keith so you may want to call him at 262-3268 to see if he's recommending anyone else for your 2nd & 3rd estimates.

Installers have a couple constraints. You can tell them what you want but they have to install a system that'll pass HECO's requirements (or you won't get your rebate). For your size home they'll probably want at least two 3'x8' panels (maybe two 4'x8's) and a 120-gallon heater. We don't use that much hot water at our home but HECO oversizes the specs in case your home someday houses the whole ohana. So they're not upselling you, they're trying to pass the inspection. On cold, wet winter weeks (when it rains for four days in a row) you'll be glad you have the 120-gallon heater. Our 80-gallon model barely made it through 2006's 40 days of rain.

The tax credits are handed out by calendar year, so the contractors are humongously busy in Oct-Dec and considerably more flexible in Jan-Mar. You might get a rush job now but they might be running special deals early next year-- it depends on the contractor.

The contractor's profit margins are all about speed, which is all about ease of installation and special ($$) training/tools. They may not want to use the "solar ready" pipes inside your house because they don't know their condition. They may want to route their pipes a certain way because it's faster/easier, and screw the aesthetics. Other customer requests may be gently turned down for the same concerns. If your home doesn't fit into one of their standard designs then they don't want to deal with you (or the price will rise considerably).

You may need a Hawaii state construction permit and the permission of your community association (I don't know the solar water rules anymore). I had decided to run my own construction permit and quickly found out that the office didn't want to deal with homeowners and their backlog would make me wait for days (literally). Meanwhile the solar contractors have all filed pre-approved plans with the permit staff and they use "runners" (people paid to stand in line and process the permit) so they're done very quickly. It was worth every penny of the $452 that I paid Keith for the permit process, and unless you're an insider or have a very good contractor connection then you'll probably find it worth every penny to pay a similar fee. But the contractors won't touch the community associations, so if you have to deal with one then you're on your own.

Panels can last a very long time (ours are third-hand from the late 1970s or early 1980s) or they'll fall apart in the first five years. If they make it through the first five years then they're good for at least two more decades. Thermodynamics is thermodynamics and you probably have plenty of sun, so you care the most about the quality of the soldering on the copper piping inside the collector. You don't care so much about the metal heat-transfer surface, the insulation, the cover glass, or even the box. Some companies will sell you panels made almost entirely of copper (or even brass) with the world's most expensive insulation & cover glass, but you want piping joints that don't spew water. If you want to see different panel designs, go down to InterIsland Solar in Mapunapuna and ask to see their cutaway models.

If you have any hard-water concerns in your neighborhood then I highly recommend a whole-house water conditioner (ion-exchange resin with salt). They only cost about $500 (at Home Depot!) but they'll greatly extend the life of your panels and your water heater by keeping the minerals out of them. They'll also help buffer the water's pH to avoid acid-pitting corrosion of the collector's copper pipes (and your house plumbing). Otherwise your panels can die of calcium atherosclerosis within 20 years. Tell the contractor you want them to check your house for hard water.

The solar water pump can run off AC (plugged into a controller) or DC (from a small PV panel on the roof next to your water panels). Four years ago there was a lot of concern about the reliability of DC pumps, so most contractors were using AC. A DC pump means that you'll still be making hot water even if HECO is offline, but you have at least a day or two of hot water in the tank anyway. So don't let the contractor scare you into a (more expensive) DC pump. Our AC pump is at least four years old, it even sat dry for several months before we bought the tank, and it's still been running fine.

I'm not sure how long the federal tax credits will be in effect. They're currently scheduled to expire at the end of 2008 (http://www.dsireusa.org/library/includes/incentive2.cfm?Incentive_Code=US37F&State=Federal&currentpageid=1) but they may be renewed. That DSIRE website also lists state tax credits (http://www.dsireusa.org/library/includes/map2.cfm?CurrentPageID=1&State=HI&RE=1&EE=0).

PM me if you have more solar water questions. Photovoltaic-- that's a whole 'nother thread.


And while we're on the subject of electrical costs, forget the notion that you'll save energy by using your electrical appliances during non-peak hours. Unless you have a demand recorder attached to your electric meter and you have a provision in your HECO account to be discounted for use during those non-peak hours, you won't see any change in your electric bill no matter what time of the day you blow out those Kilowatts.
If HECO tells you your energy costs can go down by running your appliances during non-peak hours, then call them up, request a demand recorder (a device that records usage in hourly, daily, weekly units) and to go on a billing program utilizing off-peak metering savings.
HECO's blessed us with a digital meter that's hypothetically capable of time-of-day metering, but HECO hasn't said anything about the program. Do you know where I can find out more or who I'd want to talk to?

oceanpacific
August 10th, 2007, 08:25 AM
We have two 4'x8' water panels and 3000 watts of grid-tied photovoltaic panels on our Mililani south roof. We've had the PV running since early 2005 and the water since early 2006. The water panels are at the top of the 2nd story (http://i11.photobucket.com/albums/a191/Nords_Nords/Solar%20photovoltaic%20array%20expansion/Allpanels.jpg). Last month's electric bill was $18 but this month's will probably be lower.

You may need a Hawaii state construction permit and the permission of your community association (I don't know the solar water rules anymore). I had decided to run my own construction permit and quickly found out that the office didn't want to deal with homeowners and their backlog would make me wait for days (literally). Meanwhile the solar contractors have all filed pre-approved plans with the permit staff and they use "runners" (people paid to stand in line and process the permit) so they're done very quickly. It was worth every penny of the $452 that I paid Keith for the permit process, and unless you're an insider or have a very good contractor connection then you'll probably find it worth every penny to pay a similar fee. But the contractors won't touch the community associations, so if you have to deal with one then you're on your own.

If you have any hard-water concerns in your neighborhood then I highly recommend a whole-house water conditioner (ion-exchange resin with salt). They only cost about $500 (at Home Depot!) but they'll greatly extend the life of your panels and your water heater by keeping the minerals out of them. They'll also help buffer the water's pH to avoid acid-pitting corrosion of the collector's copper pipes (and your house plumbing). Otherwise your panels can die of calcium atherosclerosis within 20 years. Tell the contractor you want them to check your house for hard water.


Who installed your photo-voltaic panels? How many storage batteries and where are they located?

Any problems getting your design pass the Mililani Town Association (MTA) guidelines? Mine was part of an extensive re-modeling project and I made sure that the design showed the panels were mounted with the bottom edges parallel with the edge of the roof (MTA is extremely sensitive to aesthetics over efficiency). The copper pipes were run in the walls (out of sight). The sturdier type-L grade rather than the softer type-M.

My mounting rails are anodized aluminum instead of painted 2" x 4" lumber, secured through a resin-filled PVC cup to the roof rafters with 6" lag bolts instead of to the roof sheeting. The panels are secured with stainless steel clips and bolts.

These are some of the features of first-line installation over a run-of-the-mill job.

WindwardGamer
August 10th, 2007, 08:48 AM
Great info here coming in, thanks a lot, learning much... :)
I need to do some research, for example I don't even know if the typical solar heating system replaces the electric water heater, or just during the daytime, or splits the load... those long stretches of rain could be tough if it means shortage of hot water, lol...

Linkmeister
August 10th, 2007, 09:19 AM
We've had solar for years, and our electric bill is still way above the "average" we see quoted in the paper when there are articles about HECO's rates. It's frustrating.

Everybody's situation and usage is different; we have a pool with a pump, for one thing.

Anyway, we had ours installed by Pancho, and we've always had good R&M from his company when it's been needed.

Pretender
August 10th, 2007, 01:25 PM
In most homes, water heating and refrigeration are the two top electricity consumption categories. If you have a pool, the pool is number one.

oceanpacific
August 10th, 2007, 02:59 PM
Great info here coming in, thanks a lot, learning much... :)
I need to do some research, for example I don't even know if the typical solar heating system replaces the electric water heater, or just during the daytime, or splits the load... those long stretches of rain could be tough if it means shortage of hot water, lol...

The solar water heater has an electrical element as a "back-up" to heat water during cloudy and/or rainy days. A timer is utilized to limit this to a certain "peak" period such as 6:00-8:00 pm IF the water temperature goes below a certain pre-set number, such as 120 degrees. If the water temperature is above that, the electrical back-up is inoperative.

Nords
August 10th, 2007, 05:55 PM
Who installed your photo-voltaic panels? How many storage batteries and where are they located?
Any problems getting your design pass the Mililani Town Association (MTA) guidelines? Mine was part of an extensive re-modeling project and I made sure that the design showed the panels were mounted with the bottom edges parallel with the edge of the roof (MTA is extremely sensitive to aesthetics over efficiency). The copper pipes were run in the walls (out of sight). The sturdier type-L grade rather than the softer type-M.
My mounting rails are anodized aluminum instead of painted 2" x 4" lumber, secured through a resin-filled PVC cup to the roof rafters with 6" lag bolts instead of to the roof sheeting. The panels are secured with stainless steel clips and bolts.
These are some of the features of first-line installation over a run-of-the-mill job.
Island Energy did the electrical work (attaching the inverter to the wall and connecting the first 1100 watts of panels to the inverter). We did all the mechanical work (mounting the panels, routing the wiring & conduit) and Keith was way patient with us as he made sure it was all up to code. HECO's net-metering agreement requires a construction permit # and an electrician's contract license # as part of the deal.

No storage batteries. It's grid-tied, which is why we have a digital meter and we're interested in off-peak metering. We still draw power from the grid when we use more than we make (at night), and HECO compensates us KWHr-for-KWHr when we pump power into the grid. We just got our electrical bill for July, where we generated 300 KWHr and used 303 KWHr. So HECO's charge for those three KWHr is the $16.99 minimum monthly charge for being connected to their grid. Grid-tie gives a rock-solid bus voltage for start-up surges (like fridges & vacuum cleaners) so we don't have to worry about house bus voltage fluctuating too much. Besides I dealt with batteries during my time in the submarine force and I have no desire to go there again.

No problems with MTA. Our house was built with solar water plumbing from the roof to the garage so we just blew out the lines and connected them. I used a pressure-testing rig to check both 4'x8' panels before we hoisted them on the roof. (Tested sat, but lifting them up was ugh.) We used the thicker copper pipe because I don't want to be chasing leaks 25 years from now. The rails & mounts are anodized aluminum & stainless fasteners left over from a lanai-enclosure project. It's probably overkill but I don't want to have to do it again after the hurricane. It was a bit of pressure, though, drilling all those holes in a perfectly good roof.

Copper pipe & fittings came from Home Depot. We bought valves & the controller from InterIsland Solar Supply. Since we did our own work we didn't apply for the HECO rebate, but we brought the whole system in for $919.81.

The solar water's rooftop piping insulation is starting to crumble from 18 months of UV exposure. I've been told that it should be painted to protect it, which is perhaps a construction detail that should be checked with an installer. They won't be expecting that question!


Great info here coming in, thanks a lot, learning much... :)
I need to do some research, for example I don't even know if the typical solar heating system replaces the electric water heater, or just during the daytime, or splits the load... those long stretches of rain could be tough if it means shortage of hot water, lol...
Yep, what Ocean Pacific said. A solar water heater still has an electric heating element in it that comes on when the tank gets colder than your setpoint (say, 105 degrees). You can also put the electrical feed through a timer (like the "Little Gray Box") to only turn on the electric heater in the tank if the temp is both below 105 degrees and it's between 6-8 PM.

I say 105 degrees because that's as low as my family will tolerate, and by that time of day if the sun hasn't broken through then it's too late. It happened twice during the 40 days of rain last year, and it hasn't happened again since.

oceanpacific
August 10th, 2007, 07:00 PM
Thanks for the info. We'd be interested in setting up a similar system to control our electrical cost. Our HECO bill is average as the savings from water heating is used to operate some of our air conditioners when things really get humid. We don't use the AC all that often as our ceiling fans in conjunction with good cross-ventilation have kept things comfortable. Although I'm pre-wired for split-AC systems (e.g. Mitsubishi's Mr. Slim), I've managed to avoid that major expense for the last thirteen years. I've got better things to spend $10K on!

A lot of the fly-by-night door-to-door solar companies have been weeded-out by now. Oh, the stories I could tell! APOLLO was successful because they were recommended by many satisfied customers wlling to give out referrals. This included a good number of engineers, general contractors, and financial consultants.

After Hurricane Iwa in 1982, they got a lot of work in Kauai replacing systems which got blown off roofs, none of which were their installations.

craigwatanabe
August 10th, 2007, 07:46 PM
HECO's blessed us with a digital meter that's hypothetically capable of time-of-day metering, but HECO hasn't said anything about the program. Do you know where I can find out more or who I'd want to talk to?

Your digital meter won't do demand recording unfortunately. The supplier is Westinghouse in most cases and the remote reading equipment built into it is from ITRON and they're not in the demand recording biz.

Most demand recording accounts are with large commercial accounts that utilize a form of interruptable accounting system. This system allows the utility to cut or reduce the amount of energy supplied to that client when peak demands require that reduction to keep the grid afloat.

The client in return uses their own electrical generation during this time period. With this agreement in place, the client is given a reduced usage bill. The problem is that typically the client won't switch off during these periods so demand recording is necessary from the utility's perspective to ensure the client follow their agreement.

The Gas Company uses this system when peak demands create a drop in utility pressure in the gas lines around Honolulu. Large users are given an opportunity to use their own gas supply or alternate energy source to keep their systems up and running during peak loads.

This is one of the reasons why large commercial cleaners run their operations late at night where there are no demands on utility usage, plus these clients get a discount on their consumption.

As for residential, I don't know if HECO accomodates residential customers. The Gas Company didn't.

Nords
August 10th, 2007, 09:18 PM
Your digital meter won't do demand recording unfortunately. The supplier is Westinghouse in most cases and the remote reading equipment built into it is from ITRON and they're not in the demand recording biz.
Well, bummer. The old analog meter was more fun because you could watch it spin backwards and do the engineer's dance of joy. The new meter just cycles among LCD displays.

The HECO installation tech had said that the company had plans to do time-of-day metering but he had no idea when that would happen. The meter timestamps something like every 15 seconds and again is hypothetically capable of reporting its history over a network or into a meter reader's gear.

The problem with being an early adopter is that few authorities understand what you're doing and may even be suspicious of your results. The city permit people didn't know how to approve a PV array installation and kept confusing it with solar water. (Another reason I was so glad to pay Keith Cronin-- they already had plans & permits on file with the city.) When our PV array was installed the permit inspector came out and admitted he knew nothing more than to check that it was properly grounded. It was only the second PV system he'd seen. Six weeks after it was installed, HECO's theft-prevention unit came out to check why our consumption had dropped off so dramatically. Apparently his department didn't know that we had a net-metering agreement with another HECO department so they drove the company car up from Pearl City to do some sleuthing. And last year a survey group collected data on PV installations by checking net-metering agreements-- there were only 26 of them on the entire island of Oahu. But hopefully that's ramping up.

craigwatanabe
August 10th, 2007, 09:25 PM
Those Honolulu inspectors should pay the Big Island a visit as there are a lot of residents on net metering.