Yesterday, Melissa at the Sunergy Systems office faxed completion paperwork to Snohomish County PUD.
Today, we're getting the PUD post-inspection visit. Hillary and Aaron just need to take a couple photos of the PV inverter and SWH tank. This step authorizes the incentive payments and meter installation.
Then, hopefully this week, the production meter will get installed by PUD. We apparently won't get any notice for this last visit, since they don't need any interior access.
Tuesday, June 30, 2009
Monday, June 29, 2009
Water heat system optimization
We heard the water heater electrical element can be left off 3 to 4 months out of the year in our area, thus heating entirely by solar, so we've been giving that a try. [Corrected 7/11/09: not 8 months as originally posted.] We shut off its big 240V double-switch circuit breaker. (The solar pump station is still on, powered by a separate 120V circuit.)
The past few days, the weather has been sunny and clear, and each afternoon we noticed the SWH rooftop collector temperature got around 300 degrees F ... and higher!
The tank was already at the (default) maximum 140 degrees F, and we weren't using much hot water, so the pump shut off and the caution icon flashed on the LCD panel. (We called Steve at home, and he reassured us this was normal, and the system is designed for hundreds of degrees more.)
Why leave the heat in the rooftop collector, which just gets lost in the evening? Seems like a "waste," right? Steve and Jeremy stopped by today to make a simple programming adjustment on the pump: The tank maximum was increased to 155 degrees F.
This approach seems smarter:
The past few days, the weather has been sunny and clear, and each afternoon we noticed the SWH rooftop collector temperature got around 300 degrees F ... and higher!
The tank was already at the (default) maximum 140 degrees F, and we weren't using much hot water, so the pump shut off and the caution icon flashed on the LCD panel. (We called Steve at home, and he reassured us this was normal, and the system is designed for hundreds of degrees more.)Why leave the heat in the rooftop collector, which just gets lost in the evening? Seems like a "waste," right? Steve and Jeremy stopped by today to make a simple programming adjustment on the pump: The tank maximum was increased to 155 degrees F.
This approach seems smarter:
- The heat gets moved into the super-insulated tank (when idle, Steve says the tank located indoors will lose only half a degree F per hour).
- The tank can take the heat (less than boiling, 212 degrees F). This fact is further evidenced by the electric element thermostat which is adjustable up to 180 degrees F.
- The adjustable mixing valve on the tank hot water output makes a safe, consistent temperature. We've played with a thermometer at the tap and rotated the mixing valve so we're at about 125 degrees F. (We might temporarily adjust it up while running the dishwasher, which would shorten the dishwasher run cycle since it won't have to heat up the water.) [Clarification 7/11/09: With the tank temp @ 155 F, the resulting mixer valve range is about 130 to 150 F at the tap.]
Saturday, June 27, 2009
What Happened When
This blog was started when we were already pretty far along. Here's a timeline of our major milestones:
- Many years: Think about how our south-facing roof would be perfect for solar stuff; we first replace our roof (2007) and windows (2008)
- April 2009: Discovery of utility incentives, web research, contractor selection
- April 28: Contacted Sunergy Systems; sent our electric bill history for the last year
- May 5: On-site solar consultation with Ilan, including rooftop shade analysis
- May 8: Checked out a prior installation; decided we want Evergreen black-framed PV modules (same price and 25-year warranty as silver-framed; should look better on our roof)
- May 11: Contract signing, deposit payment
- May 15: Site visit by Sunergy engineers Jon (PV) and Steve (SWH); another shade analysis; system physical layout determined
- May 25: Made our own circuit list (we flipped each circuit breaker to figure out what it's for, to assist the electrician later)
- May-June: Spend lots of time cleaning up areas around the house that will need access (away from water heater, electric panel, attic access panel, roof access, etc.)
- June 5: Payment for materials order
- June 12: Completed paperwork sent by Sunergy to PUD (cutting it close for our scheduled install; PUD normally wants 4 weeks, but we're OK with less because we're not doing the PUD loan)
- June 17: PUD site pre-inspection by Hillary and Aaron, including rooftop shade analysis, taking a picture of the existing water heater, and general energy efficiency audit (measuring windows and insulation)
- June 23: PUD approves projects, and shares audit recommendations
- June 24: Installation by Sunergy begins
- June 25: SWH completed and operational
- June 26: PV panels and wiring completed; state L&I electrical inspection
- Upcoming: Customer care package delivered by Sunergy (manuals, warranties, etc.)
- Upcoming (June/July): For the PV "5101" Washington Production Incentive, we'll get some form from the state Department of Revenue, which gets faxed to Sunergy, who completes it and sends it to PUD. Not sure yet if we'll need to re-send the form to PUD every year thereafter.
- Upcoming (July): PUD site post-inspection
- Upcoming (July): PUD meter installation; PV finally operational; final payment to contractor
- Upcoming: PUD incentive payments received
Cost and Payoff
Friends and neighbors keep asking us about costs and payback time. There's the old saying "you need money to make money," and that certainly applies here. Despite all the credits, exemptions, and incentives, there's still significant up-front costs.
The short answer is that it's about the cost of a new car -- but a big difference is that the car doesn't pay for itself over time. Here's more detail for our specific situation.
Up-Front Costs:
Power Generation (3.3 kW): $25,511
Water Heat (30 tube system): $9,053
Total Initial Cost: $34,564
Includes all equipment, engineering, installation, permits, fees, etc.
Expected Year One Payback (July 2009 through June 2010):
PUD PV incentive: ($1,650) *
PUD SWH incentive: ($500)
IRS 30% credits: ($10,369) **
Generation: ($300) ***
WA "5101" rebate: ($537) ****
SWH savings: ($218) *****
Total 1st Year Payback: ($13,574)
*Snohomish County PUD incentive of $500 per rated kW, which is prorated for partial kW. We opted for the cash incentive instead of PUD 2.9% loan program.
**The $2K caps for solar were removed in 2009 economic stimulus legislation. Federal tax credit offsets income tax due (it's not a deduction); big credit may actually need to be spread over a couple tax years.
***Savings based on current utility rates (winter $.08367/kWh and summer $.08053/kWh as per PUD residential schedule), plus 6% city utility tax, and 3,450 kWh/year estimated generation based on our system size, efficiency, pitch, orientation, shading, etc.
****Washington Production Incentive at base rate $.015/kWh with out-of-state components, extended to June 2020 in 2009 state Senate Bill 6170. You get paid to generate solar power, even if you use it yourself!
*****Estimated 2,508 kWh/year savings with 2-4 person solar water heat system.
Expected Payback For Subsequent Ten Years (July 2010 through June 2020):
If PUD rates don't go up [yeah, like that'll happen]: ($10,550)
If PUD rates go up on average 2%/year: ($11,155)
If PUD rates go up on average 6%/year: ($12,607)
These are cumulative totals for 10 years, not annual amounts.
Since we paid $1,035 to PUD for the most recent full billing year (and that's before the rates went up in April), we'll be effectively zeroing out our electric bill. The combined system can pay for itself in 15 to 20 years, although this varies depending on your assumptions (for example, we're not including loan interest above, the system age may diminsh generated power levels, and who knows if the production rebate will be extended again beyond 2020). Any years after the payoff point are gravy (the PV modules have a 25-year warranty for 80% generation, but should last even longer).
About 10-15 years out, we're expecting to replace a couple components (water tank and PV inverter), so we'll need to set aside some of the savings towards those future costs. We're assuming we won't be selling or moving before then (although, if we do, we should be able to recover the cost on resale).
Of course, besides the financial upside, there's the environmental benefits, and the joy and peace-of-mind that will last longer than a new car or expensive vacation.
The short answer is that it's about the cost of a new car -- but a big difference is that the car doesn't pay for itself over time. Here's more detail for our specific situation.
Up-Front Costs:
Power Generation (3.3 kW): $25,511
Water Heat (30 tube system): $9,053
Total Initial Cost: $34,564
Includes all equipment, engineering, installation, permits, fees, etc.
Expected Year One Payback (July 2009 through June 2010):
PUD PV incentive: ($1,650) *
PUD SWH incentive: ($500)
IRS 30% credits: ($10,369) **
Generation: ($300) ***
WA "5101" rebate: ($537) ****
SWH savings: ($218) *****
Total 1st Year Payback: ($13,574)
*Snohomish County PUD incentive of $500 per rated kW, which is prorated for partial kW. We opted for the cash incentive instead of PUD 2.9% loan program.
**The $2K caps for solar were removed in 2009 economic stimulus legislation. Federal tax credit offsets income tax due (it's not a deduction); big credit may actually need to be spread over a couple tax years.
***Savings based on current utility rates (winter $.08367/kWh and summer $.08053/kWh as per PUD residential schedule), plus 6% city utility tax, and 3,450 kWh/year estimated generation based on our system size, efficiency, pitch, orientation, shading, etc.
****Washington Production Incentive at base rate $.015/kWh with out-of-state components, extended to June 2020 in 2009 state Senate Bill 6170. You get paid to generate solar power, even if you use it yourself!
*****Estimated 2,508 kWh/year savings with 2-4 person solar water heat system.
Expected Payback For Subsequent Ten Years (July 2010 through June 2020):
If PUD rates don't go up [yeah, like that'll happen]: ($10,550)
If PUD rates go up on average 2%/year: ($11,155)
If PUD rates go up on average 6%/year: ($12,607)
These are cumulative totals for 10 years, not annual amounts.
Since we paid $1,035 to PUD for the most recent full billing year (and that's before the rates went up in April), we'll be effectively zeroing out our electric bill. The combined system can pay for itself in 15 to 20 years, although this varies depending on your assumptions (for example, we're not including loan interest above, the system age may diminsh generated power levels, and who knows if the production rebate will be extended again beyond 2020). Any years after the payoff point are gravy (the PV modules have a 25-year warranty for 80% generation, but should last even longer).
About 10-15 years out, we're expecting to replace a couple components (water tank and PV inverter), so we'll need to set aside some of the savings towards those future costs. We're assuming we won't be selling or moving before then (although, if we do, we should be able to recover the cost on resale).
Of course, besides the financial upside, there's the environmental benefits, and the joy and peace-of-mind that will last longer than a new car or expensive vacation.
Friday, June 26, 2009
Interconnection illustrated
Here's a diagram that shows how the PV components connect together. (Source: Snohomish County PUD)
Solar panel system (kinda) finished
We've got a total of 16 Evergreen 205W modules. Each panel was independently tested prior to installation.
The solar panels were installed on the rails by Jon and Michael.
To ensure completion by inspection time, there was no lunch break today.
The system was briefly tested, and we saw our (net) meter run backwards! We even captured this moment on video:
The state L&I inspector said he loves PV systems (this was his fifth PV inspection this week alone). He wanted grounding changes in a couple spots. Fortunately, these changes were completed immediately without requiring an additional separate inspection. We got the official approval stickers!
Now, here's the excruciating part: We have to wait before the PV system is operational. PUD has to come out twice more (two separate visits by different departments) for an incentive program inspection and the production meter installation. We don't know yet if that will be finished before or after July 4th.
The solar panels were installed on the rails by Jon and Michael.
To ensure completion by inspection time, there was no lunch break today.
The system was briefly tested, and we saw our (net) meter run backwards! We even captured this moment on video:
The state L&I inspector said he loves PV systems (this was his fifth PV inspection this week alone). He wanted grounding changes in a couple spots. Fortunately, these changes were completed immediately without requiring an additional separate inspection. We got the official approval stickers!
Now, here's the excruciating part: We have to wait before the PV system is operational. PUD has to come out twice more (two separate visits by different departments) for an incentive program inspection and the production meter installation. We don't know yet if that will be finished before or after July 4th.
Thursday, June 25, 2009
Install progress for photovoltaics
We'll have the PV modules on two different roofs. After deciding on the (aesthetically and technically) best route, conduit was installed to carry wiring from the upper level roof to the lower level. Because of our property's peculiar lines of sight, you don't really notice it from the street or backyard. The conduit can be painted later.
Ground wires (for lightning safety) were pulled and connected to rails, and a supplemental 6-foot ground rod driven into the ground.
To carry wiring, there's nice flashing that will be tucked under the panels.
A junction box is also on the roof, where it all connects together on the way to the inverter.
Tomorrow's plan is to get the panels on the rails, and an official inspection.
Ground wires (for lightning safety) were pulled and connected to rails, and a supplemental 6-foot ground rod driven into the ground.
To carry wiring, there's nice flashing that will be tucked under the panels.
A junction box is also on the roof, where it all connects together on the way to the inverter.
Tomorrow's plan is to get the panels on the rails, and an official inspection.
Install finished for water heat
The Apricus glass tubes have copper innards (which heat up the transfer fluid that flows near the copper ends). While these tubes were on the ground, you could feel the copper ends getting warm (even though it's a cloudy day).
The tubes are lubed and installed into the rooftop array by Steve and Jeremy. The tubes do admittedly look a bit phallic, especially with those rubber caps on the lower ends.
Because our roof has low 4:12 pitch (22 degrees), there's a low-angle kit for near-optimal sunlight (7:12, or 30 degrees). The tube array is positioned away from the upper story (and adjacent PV modules) to minimize shading effects. All 30 tubes are installed. It looks like a rooftop rocket launcher, ready for July 4th!
A new electrical outlet was installed for the pump station (rated a mere 0.8 Amps). The system was charged with fluid flowing even before all the tubes were installed. After air was bled out, the pump runs very quietly. Lastly, seismic safety straps were installed around the tank.
The system uses temperature sensors in the collector array, tank bottom, and tank top so it knows when to activate the pump. Other than doing a fluid pH (acidity) check in a few years, and a normal annual sediment flush as with any tank, there's really nothing else to do.
One last interesting bit is the mixing valve on top of the tank. Sorta like a vehicle thermostat spring, it opens to let in cold water if the hot water is too hot. It will keep the hot water output temperature consistent (whatever you select between about 120 and 140 degrees F), even though there can be big variations within the tank. As a result, you don't waste too-hot water with manual mixing at tap.
The tubes are lubed and installed into the rooftop array by Steve and Jeremy. The tubes do admittedly look a bit phallic, especially with those rubber caps on the lower ends.
Because our roof has low 4:12 pitch (22 degrees), there's a low-angle kit for near-optimal sunlight (7:12, or 30 degrees). The tube array is positioned away from the upper story (and adjacent PV modules) to minimize shading effects. All 30 tubes are installed. It looks like a rooftop rocket launcher, ready for July 4th!
A new electrical outlet was installed for the pump station (rated a mere 0.8 Amps). The system was charged with fluid flowing even before all the tubes were installed. After air was bled out, the pump runs very quietly. Lastly, seismic safety straps were installed around the tank.
The system uses temperature sensors in the collector array, tank bottom, and tank top so it knows when to activate the pump. Other than doing a fluid pH (acidity) check in a few years, and a normal annual sediment flush as with any tank, there's really nothing else to do.
One last interesting bit is the mixing valve on top of the tank. Sorta like a vehicle thermostat spring, it opens to let in cold water if the hot water is too hot. It will keep the hot water output temperature consistent (whatever you select between about 120 and 140 degrees F), even though there can be big variations within the tank. As a result, you don't waste too-hot water with manual mixing at tap.
Installer selection
We don't want to sound like an advertisement, but here's why we chose Sunergy Systems:
- On our utility's approved installer list.
- Lots of positive customer ratings.
- Experience, certifications, and familiarity in working with the local utility and incentive programs. We're willing to pay a little more to ensure things go smoothly.
- Several residential installations in our area. We remember this company from a local/online "solar homes tour" a few years ago.
- When we called the Sunergy office, we spoke with a person immediately.
- Our solar consultant (sales person) provided several options, was easy to work with, and was able to address our questions.
Why are we doing this now?
In this time of pay cuts and looming layoffs, it seems a bit ambitious to do this project, but here's why the timing seems right:
- Income tax credits (not deductions) for 30% of costs for solar systems. The 2009 economic stimulus package removed the $2K cost limit caps.
- Utility incentives for solar systems. Snohomish County PUD Solar Express program launched in March 2009. We know from past experience that PUD programs can eventually run out of funding, so we didn't want to miss out this time.
- Washington State "5101" Production Incentive (minimum $0.15/kwH generated, even if we use it ourselves!) has been extended to 2020. The sooner we install, the more time for payoff.
- Washington State sales tax exemptions (solar water heat ends June 2009; photovoltaics extended to June 2013). With our current sales tax rate of 8.6%, this is pretty significant.
- The cost of photovoltaic modules has dropped significantly over the last 6 to 12 months.
- We already replaced our roof in 2007. (PUD incentive program requires at least 15 years remaining roof life.)
- We need a new hot water heater anyway (our old tank has 6 year warranty, but it's now more than 10 years old and isn't working as well).
- We already took some steps to reduce our electrical demand (such as replacing old windows).
- Low interest rates for loans (we were already thinking about refinancing our mortgage anyway, but the final push was deciding to use it to fund our solar projects too; we prefer the longer loan term compared to PUD's 2.9% 10-year program). We think inflationary pressures will push up borrowing costs in the coming years.
- Utility electric rates will continue to increase. Although we've historically had cheap hydroelectricity in the Northwest, those days are over. Local utilities will need to fund new generation sources as demand increases. Nationwide "smart grid" and greenhouse gas "cap and trade" policies may drive up local rates in the future.
- It's good investment for ourselves, our home, the environment, local business, and America. We'll get a guaranteed return (unlike other investments these days), and it should hold its value (unlike a car).
- It's cool and the right thing to do. More "renewables" means less pressure on utilities to build plants that generate CO2 emissions.
Wednesday, June 24, 2009
Installation Day One
The electrician, engineers, and other installers from Sunergy Systems started showing up at 8:00 AM.
For the photovoltaic modules, the roof rail system takes the most time to install. The rail mounts are bolted through the roof into the rafters for structural soundness. There's rubber washers above and below the bolt, so we're not concerned about leaks.
Rails are installed on both the upper and lower roofs.
For the photovoltaic modules, the roof rail system takes the most time to install. The rail mounts are bolted through the roof into the rafters for structural soundness. There's rubber washers above and below the bolt, so we're not concerned about leaks.
Rails are installed on both the upper and lower roofs.
Carol, the electrician from Sunergy, has combined a couple circuits, moved around curcuit breakers, and eliminated an unused spare to accommodate a new double switch (240-volt, between the solar production and the utility net meters).
A new production meter will eventually be installed, and the existing meter will be changed by Snohomish PUD (so it can go backwards for "net metering"). We were approved without exterior AC disconnect switch because the SMA inverter will safely auto-disconnect when utility power is out (not backfeed into the grid when lines are being worked on). [Clarification 6/26/09: The PUD handbook says: "The PUD does not require an AC disconnect."]
Our inverter (with DC disconnect switch) is installed in the garage, which should extend its life (instead of being exposed to hot sun on the exterior south wall).
The solar water heater tank is in, plumbing connected, and the electric element is working. The solar heat transfer system is not yet finished or connected. This 80 gallon tank is bigger than our old 50 gallon tank, but still fit in nicely. The small blue tank on top is an expansion tank for safety.
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