Solar energy - your experience?

[Koolau]

One thing that makes one ponder. Hawaii electric rate is 32.76c/kWh, according to this.

It would want to install a solar system even more than I would in California. Throw a big battery in there too.

Of course, if you don't have room for the panels, then there's not much to do. But if I had a suitable home, I would have panels all over the place.

True. Of course, our building is condo and there would be no way to add individual apartment solar arrays. We could deploy a lot more solar in the Islands because of our climate, but again, HECO can (or will) only accept so much. I think it will take a totally rebuilt "grid" to manage any significant amount of solar energy. Storage is also a main issue like anyplace else. The technology is available but still isn't as robust as probably needed to eventually replace our dependence on oil (maybe 85 to 90% of our energy usage).

 

[Scuba]

^^^ While electricity is expensive in Hawaii, you don't use that much to make it worthwhile to have AC. Some poor Californians have to run AC.

Here's one of the 3 TOU rates from SCE (Southern California Edison).

June to Sep TOU-D-4-9PM: 44c/kWh for peak period of 4-9PM, 27c/kWh off peak.

Wowza!

My Phoenix TOU rate in July-Aug is this: 24c/kWh for 2-8PM, 7.3c/kWh off peak.

The peak rate is less for the shoulder months of May, June, Sep, Oct at 21c/kWh. For the winter months, the difference between on-peak and off-peak is a lot less.

If I had to pay the SCE rate, using my usage in Sep 2018 (prior to having my solar system), I compute the monthly bill to be close to $800.

PS. In several of our trips to Hawaii, although we were either right on the beach or in a Waikiki high rise, I still wanted to have the AC on. It's because of the humidity. I am so used to the dry air of the Southwest.

This is exactly why we are looking at solar.

 

[LoneStarJeffe]

If I were building new, I would look hard at a solar system and 24v appliances along with efficient insulation. For existing, I think you get a better ROI if you invest in more efficient appliances and insulation before you consider solar. I am not saying solar might not be a good choice. I am just saying it should not be your first choice.

 

[Koolau]

If I were building new, I would look hard at a solar system and 24v appliances along with efficient insulation. For existing, I think you get a better ROI if you invest in more efficient appliances and insulation before you consider solar. I am not saying solar might not be a good choice. I am just saying it should not be your first choice.

Sounds reasonable. Conservation is typically cheaper than adding more energy input. Building for conservation from the ground up is much easier than retrofitting an energy inefficient structure. The TRICK is to find a builder who buys into that and has experience. YMMV

 

[Scuba]

If I were building new, I would look hard at a solar system and 24v appliances along with efficient insulation. For existing, I think you get a better ROI if you invest in more efficient appliances and insulation before you consider solar. I am not saying solar might not be a good choice. I am just saying it should not be your first choice.

As part of our 2020 remodel, we put in all new energy efficient windows and doors, plus replaced and enhanced all of the insulation throughout. Even so, our electricity bills were in the $550-$750 range all summer.

 

[Koolau]

As part of our 2020 remodel, we put in all new energy efficient windows and doors, plus replaced and enhanced all of the insulation throughout. Even so, our electricity bills were in the $550-$750 range all summer.

Wow! I've forgotten how big and where your house is but that does seem high for all the work you did. Do you have a "before" comparison of e-bills? I'd like to think the extensive remodel was actually effective.

 

[Scuba]

Wow! I've forgotten how big and where your house is but that does seem high for all the work you did. Do you have a "before" comparison of e-bills? I'd like to think the extensive remodel was actually effective.

We didn’t live in the house the previous summer. It was being remodeled and the A/C was off. However I’ve seen neighbor’s posts on Nextdoor and many have bills over $1K during the summer heat. Keep in mind that it’s 115-120 here for many weeks in the heat of the summer.

 

[Koolau]

We didn’t live in the house the previous summer. It was being remodeled and the A/C was off. However I’ve seen neighbor’s posts on Nextdoor and many have bills over $1K during the summer heat. Keep in mind that it’s 115-120 here for many weeks in the heat of the summer.

Heh, heh and they say Hawaii is expensive!

Thanks for the update. It sounds like your improvements were effective.

 

[NW-Bound]

We didn’t live in the house the previous summer. It was being remodeled and the A/C was off. However I’ve seen neighbor’s posts on Nextdoor and many have bills over $1K during the summer heat. Keep in mind that it’s 115-120 here for many weeks in the heat of the summer.

Yes, I believe it. In an earlier post, I said that if I were in California and had to pay the rate by SCE, my bill would have been close to $800 without the solar system. And my house is not superbig at 2700 sq.ft.

By the way, the house was built in the 80s, and did not have dual-pane windows throughout. It had 21 windows, with 9 being dual-pane. When I changed out the 12 single-pane windows, did not see a noticeable decrease in electric bills. The installer did not promise it either. I think the heat gain/loss through the windows is not big, compared to that through the walls and ceilings. Bummer. The windows did provide superior sound insulation, however.

 

[ncbill]

If I were building new, I would look hard at a solar system and 24v appliances along with efficient insulation. For existing, I think you get a better ROI if you invest in more efficient appliances and insulation before you consider solar. I am not saying solar might not be a good choice. I am just saying it should not be your first choice.

Off-grid system would normally use 48VDC instead, for many reasons.

 

[Another Reader]

Yes, I believe it. In an earlier post, I said that if I were in California and had to pay the rate by SCE, my bill would have been close to $800 without the solar system. And my house is not superbig at 2700 sq.ft.

By the way, the house was built in the 80s, and did not have dual-pane windows throughout. It had 21 windows, with 9 being dual-pane. When I changed out the 12 single-pane windows, did not see a noticeable decrease in electric bills. The installer did not promise it either. I think the heat gain/loss through the windows is not big, compared to that through the walls and ceilings. Bummer. The windows did provide superior sound insulation, however.

That's pretty much what I have heard from people that did it out there. I really don't understand people in my subdivision in the Bay Area paying $25k or more when we have double pane original windows.

You are in the Waymo service area of Mesa if I recall. That means SRP electricity, cheap Mesa utilities, and low Mesa taxes. Plus easy access to anywhere in the Valley. Sweet!

 

[Koolau]

Yes, I believe it. In an earlier post, I said that if I were in California and had to pay the rate by SCE, my bill would have been close to $800 without the solar system. And my house is not superbig at 2700 sq.ft.

By the way, the house was built in the 80s, and did not have dual-pane windows throughout. It had 21 windows, with 9 being dual-pane. When I changed out the 12 single-pane windows, did not see a noticeable decrease in electric bills. The installer did not promise it either. I think the heat gain/loss through the windows is not big, compared to that through the walls and ceilings. Bummer. The windows did provide superior sound insulation, however.

Never checked our new windows (in our last house) for summer electricity usage BUT saw definite improvement in NatGas usage in winter. The difference in sound deadening (of the outside world) was amazing so I think the original windows must have leaked quite a bit. The old windows frosted in winter while the new ones never did. YMMV

 

[NW-Bound]

That's pretty much what I have heard from people that did it out there. I really don't understand people in my subdivision in the Bay Area paying $25k or more when we have double pane original windows.

My brothers' homes were built in later years, and had thicker walls with better insulation. And the homes came standard with double-pane windows. I don't know what their utility bills are.

You are in the Waymo service area of Mesa if I recall. That means SRP electricity, cheap Mesa utilities, and low Mesa taxes. Plus easy access to anywhere in the Valley. Sweet!

No, I am a bit west of that. Two or three years ago, saw Waymo cars running around my neighborhood quite a bit to do some street mapping I guess, but have not seen any around here recently. Not sure about their geofenced area, but it is mostly in Gilbert and Chandler, I think.

I used to live in Glendale many years ago, way up north, and happened to have SRP also. Don't know how that works.

 

[Another Reader]

My brothers' homes were built in later years, and had thicker walls with better insulation. And the homes came standard with double-pane windows. I don't know what their utility bills are.


No, I am a bit west of that. Two or three years ago, saw Waymo cars running around my neighborhood quite a bit to do some street mapping I guess, but have not seen any around here recently. Not sure about their geofenced area, but it is mostly in Gilbert and Chandler, I think.

I used to live in Glendale many years ago, way up north, and happened to have SRP also. Don't know how that works.

I'm 1989 construction, 2,500 sf single story, 2 x 4 frame, raised foundation with vents and fiberglass batt insulation, gas heat and hot water, double pane windows. At the the end of the life of the original 10 seer A/C unit, the electric bill in mid summer approached $400. Gas was minimal. The new 14 seer A/C dropped that to $175. Winter, with gas heat, is a different story...

 

[stephenson]

I priced it about six months ago - north Florida.

Cost was around 26K after the tax credit - 34 panel 10 kW system would about zero out electricity cost.

USAA would charge an additional $250 a year for the increased value of the house.

The real estate system has very little information about how the system would affect the price, but most believe it would increase the value, but not sure how much.

Payback is still around 10 years.

Most systems use micro-inverters, and panels that put out around 330-350 W/panel ... standard product lines across number companies. Most of these systems are very trouble and maintenance free - a bad inverter (most common failure) is easy to see on the system app, but does not affect the remainder of the panels - only that panel.

Hopefully there will be a bit more government subsidy via tax credit and I'm in - btw, IMO one of government's jobs is to motivate behavior - and, tax credits do this very effectively.

We recently travelled for a week in Maine - saw WAY more solar (electric) systems there than in our area. Not sure why, but it was good to see.

 

[stephenson]

Couple of adds:
- output per panel is a big component of the math, and output has been increasing - not quickly but a bit every 2-3 years
- micro inverter capacities also increasing over time to match the panel output
- micro inverters are not the only solution, but this approach seems to offer more advantages than larger inverters since the failure of one doesn’t disable the whole system
- IMO battery cost and failure is simply too high
- composite shingle roof installations are easy, but I’ve also seen racking installed on the seams of standing seam metal roofs
- the best shingle roof to install on is a new one, in order to put off removing the panels to replace the shingles
- satellite photography tends to show PV panels withstand hurricanes better than shingles
- the output of PV cells tends to degrade over time, so try and size to a future date
- our power company requires liability insurance over 10 kW

I wish I could DIY with 8-9’ height … turn it into a shaded area and have far easier access! Way lower cost - and fun!

BTW - DON’T rent! Try to buy without loan for ease of transfer.

 

[anothercog]

Where in the Bay Area? Which contractor and what was the cost per watt?

My problem is gas heat in the winter complicates the cost-benefit analysis. The house is not well ducted, so the bedrooms use supplemental electric space heaters overnight. Add in a 32 year-old tile roof and the cost of either replacing the entire roof or just the underlayment, and I keep putting it off.

I went with SunRun. They were the most expensive of the proposals I received but others in my neighborhood that used them seemed happy, plus it was a deal through Costco which gave me a bit more comfort.

In any event, it is a 6.48kw system with estimated production of 8600kwh which is somewhat close to my annual use. Costs were around $30k. I'll get a federal rebate, a Costco cash card and supposedly another $1k rebate from my city if funds haven't run out.

However, I failed my inspection the other day. The problem was the EV charger I asked SunRun to install. I only have 125 amp service (or maybe 130). 90 amp goes to the house, 35 amp for the solar system and then 40amp for the EV charger. However, they didn't factor in the 40a breaker for the EV charger because it was installed after the site plan was finished and they didn't account for it. So I need to upgrade my panel (or worse increase my service from PG&E). I don't have a clear answer on that yet though I'm glad the EV charger was installed prior to the solar panels because part of SunRun's higher prices is that they will provide a subsidy for a panel upgrade.

If I hadn't installed the EV charger, it would have passed inspection but then I would not have had the space in my panel for the EV charger and it would have been solely at my cost to upgrade.

However, still waiting to see if SunRun will honor the subsidy to rectify the issue. Until then, I have some shiny panels on my roof not generating any power.

 

[NW-Bound]

I went with SunRun...

...it is a 6.48kw system with estimated production of 8600kwh which is somewhat close to my annual use.

Do you still get net metering, where a kWh you pump into the grid cancels out a kWh you draw from it later?

Most places no longer provide that. Instead, you get the credit in dollar amounts that your solar kWh is worth at the time it is pumped into the grid, to offset the cost of the kWh that you draw later.

Solar power is dirt cheap early in the day, when the sun is high and nobody is using much electricity. Electricity is much more expensive in the late afternoon, when people are cooking dinner and the ACs are cranking due to the houses being heat-soaked all day, and possibly charging their EV too.

It's the same as water not being worth much during a storm, but very precious during a drought.

 

[anothercog]

Do you still get net metering, where a kWh you pump into the grid cancels out a kWh you draw from it later?

Most places no longer provide that. Instead, you get the credit in dollar amounts that your solar kWh is worth at the time it is pumped into the grid, to offset the cost of the kWh that you draw later.

Solar power is dirt cheap early in the day, when the sun is high and nobody is using much electricity. Electricity is much more expensive in the late afternoon, when people are cooking dinner and the ACs are cranking due to the houses being heat-soaked all day, and possibly charging their EV too.

It's the same as water not being worth much during a storm, but very precious during a drought.

Yes, I still get the NetMetering 2 program. PG&E is lobbying hard for the less favorable NetMetering 3 program for next year. At which point solar won't be worth it.

 

[Koolau]

Do you still get net metering, where a kWh you pump into the grid cancels out a kWh you draw from it later?

Most places no longer provide that. Instead, you get the credit in dollar amounts that your solar kWh is worth at the time it is pumped into the grid, to offset the cost of the kWh that you draw later.

Solar power is dirt cheap early in the day, when the sun is high and nobody is using much electricity. Electricity is much more expensive in the late afternoon, when people are cooking dinner and the ACs are cranking due to the houses being heat-soaked all day, and possibly charging their EV too.

It's the same as water not being worth much during a storm, but very precious during a drought.

Yet another reason PVs face an uphill battle to become ubiquitous. Not sure I can blame the electric companies - they are recognizing a "reality" that they can't control. But, PV adopters want a pay back and they won't get it as quickly if their KWs get discounted by the same company that then "gouges" them later in the day. Until storage issues are "solved" I see a slowing of PV installations. Of course, I could be wrong so YMMV.

 

[Romer]

I am having Solar installed. Signed the paperwork a few weeks ago and will be installed in November

Getting a 10Kw system with 32KW of batteries with two new LG 16Kw batteries

For me, and everything is different for others, I didnt see the value to ME without the battery back up. That way in the event of a weather or hacker caused outage, I will still have power.

Batteries also allow you to draw off of them at night rather than the grid

I customized the power that stays on with the batteries. Essentially if the power goes out I still have everything except Air Conditioning, Oven and Dryer. So I have heat in the winter and if it is brutally hot, I have a nice finished basement that is always cool

I paid cash as I didnt want the lease. Since I plan on living here for as long as I am able, I wasnt concerned about resale. Payback is around 20 years, but I wanted the capability rather than it being a financial decision.

My daughter had solar on her house and paid for and it increased the value of her house when she sold it. The realtor (right or wrong) said the increase in money they would and did get back would be more than they paid for the solar system

 

[NW-Bound]

Yet another reason PVs face an uphill battle to become ubiquitous. Not sure I can blame the electric companies - they are recognizing a "reality" that they can't control. But, PV adopters want a pay back and they won't get it as quickly if their KWs get discounted by the same company that then "gouges" them later in the day. Until storage issues are "solved" I see a slowing of PV installations. Of course, I could be wrong so YMMV.

Here in Phoenix, SRP discontinued net metering a few years ago, and that really slowed down the residential solar business. Net metering is OK when only a few houses had solar. But when there are a lot of people pumping power into the grid early in the day where there's little use for it, and the same people reclaiming that power later in the day when the demand is high, that causes a real problem with the imbalance between supply and demand at different times of the day.

However, to be fair to people who installed the system in good faith when net metering was in effect, they allowed existing systems to have grandfather rights. Of course, all these were done with the agreement of the utility commission. This is the reason I built my DIY system with storage from the beginning. I can save the juice I generate early in the day to use in the late afternoon and the evening.

And speaking of solar battery, the Tesla Powerwall has several advantages. Being AC coupled, hardware wise it is really independent of the solar panels, and can be added later. The operation of the Powerwall of course should be coordinated with the panel production, but the battery and the panels can work independently. The system operation is grid-tied, but the battery can also serve as a backup power source when the grid is down. It just cannot power the whole house, and will keep only selected circuits up.

I like the way Tesla Powerwalls work a lot. However, being a non-sanctioned DIY system, my battery has to be off-the-grid, and so are the PV panels.

 

[Scuba]

Yes, I believe it. In an earlier post, I said that if I were in California and had to pay the rate by SCE, my bill would have been close to $800 without the solar system. And my house is not superbig at 2700 sq.ft.

By the way, the house was built in the 80s, and did not have dual-pane windows throughout. It had 21 windows, with 9 being dual-pane. When I changed out the 12 single-pane windows, did not see a noticeable decrease in electric bills. The installer did not promise it either. I think the heat gain/loss through the windows is not big, compared to that through the walls and ceilings. Bummer. The windows did provide superior sound insulation, however.

Interesting. Our house is slightly smaller than yours, 2600 sq ft. It may not make a big difference on the electric bill, but our 1970-built home had single-paned windows and doors. We could feel heat or cold standing next to them. With the new ones, we can’t feel anything radiating in. I agree about the sound insulation too, and our Fleetwood sliders move smoothly as silk.

 

[Scuba]

I priced it about six months ago - north Florida.

Cost was around 26K after the tax credit - 34 panel 10 kW system would about zero out electricity cost.

USAA would charge an additional $250 a year for the increased value of the house.

The real estate system has very little information about how the system would affect the price, but most believe it would increase the value, but not sure how much.

Payback is still around 10 years.

Most systems use micro-inverters, and panels that put out around 330-350 W/panel ... standard product lines across number companies. Most of these systems are very trouble and maintenance free - a bad inverter (most common failure) is easy to see on the system app, but does not affect the remainder of the panels - only that panel.

Hopefully there will be a bit more government subsidy via tax credit and I'm in - btw, IMO one of government's jobs is to motivate behavior - and, tax credits do this very effectively.

We recently travelled for a week in Maine - saw WAY more solar (electric) systems there than in our area. Not sure why, but it was good to see.

The quotes we’ve gotten are similar - about $35K for 24 panels generating about 10-15% more kWh than our current usage. $26K net of $9K tax credit.

 

[Scuba]

I went with SunRun. They were the most expensive of the proposals I received but others in my neighborhood that used them seemed happy, plus it was a deal through Costco which gave me a bit more comfort.



In any event, it is a 6.48kw system with estimated production of 8600kwh which is somewhat close to my annual use. Costs were around $30k. I'll get a federal rebate, a Costco cash card and supposedly another $1k rebate from my city if funds haven't run out.



However, I failed my inspection the other day. The problem was the EV charger I asked SunRun to install. I only have 125 amp service (or maybe 130). 90 amp goes to the house, 35 amp for the solar system and then 40amp for the EV charger. However, they didn't factor in the 40a breaker for the EV charger because it was installed after the site plan was finished and they didn't account for it. So I need to upgrade my panel (or worse increase my service from PG&E). I don't have a clear answer on that yet though I'm glad the EV charger was installed prior to the solar panels because part of SunRun's higher prices is that they will provide a subsidy for a panel upgrade.



If I hadn't installed the EV charger, it would have passed inspection but then I would not have had the space in my panel for the EV charger and it would have been solely at my cost to upgrade.



However, still waiting to see if SunRun will honor the subsidy to rectify the issue. Until then, I have some shiny panels on my roof not generating any power.

We got a quote from SunRun today. There are a couple of locally run companies here that most seem to prefer. One interesting thing is that the SunRun presentation focused almost 100% on the monthly cost. Very little was said about their brand of panels or the technical details of their system. The local companies both talked a lot about their panels and why their system works well. One uses Sunpower panels with micro inverters. The other uses Panasonic panels with one large inverter.