Pricing in Bay Area - Compared to DIY

[w00dy]

Hi,

I have been in the planning stage for several months to possibly do a DIY grid tied installation next spring. However, I also want to keep up with what some of the Solar companies might charge me as a comparison, carrot, and/or to change my mind about DIY.

I have a recent quote that seems reasonable.

3.36K system
12 280W Solarworld Panels
12 250W Enphase Microinverters

$3.50 per Watt before FTC

I have trepidation about this sizing mostly due to PG&E looking to switch to new tiers (2 standard). We currently use about 500-600KW per month and I would like to keep us at the lower cost tier. We would like to offset our power production by about 60% at a minimum.We are as energy efficient as I expect we will ever be at the moment.

Based on PV Watts this system at our location could generate 5,433 kWh per Year - which if I understand the numbers provided by PV Watts - is more than the 60% goal and is more like 80% of last years electrical use. I am OK with that based on the costs.

I do wonder what replacing one of our gas cars with an EV (e.g. low priced used Nissan Leaf) would add to our energy use. We could use the EV as our primary errands/around town car. We only spent $1200 total on gasoline last year for our 2 family cars - so we don't drive a ton, and have little to no commute. I would use the EV to replace an aging 11 year old gasoline car that gets poor sub 20mpg. The EV would account for probably 70% of our future driving needs. And the cost of the car would be offset by the amount we can sell our low mileage 2004 car.

I thought I would post my numbers to see if anyone has any comments on where we are right now - and how my numbers look.

[J.P.M.]

Hi,

I have been in the planning stage for several months to possibly do a DIY grid tied installation next spring. However, I also want to keep up with what some of the Solar companies might charge me as a comparison, carrot, and/or to change my mind about DIY.

I have a recent quote that seems reasonable.

3.36K system
12 280W Solarworld Panels
12 250W Enphase Microinverters

$3.50 per Watt before FTC

I have trepidation about this sizing mostly due to PG&E looking to switch to new tiers (2 standard). We currently use about 500-600KW per month and I would like to keep us at the lower cost tier. We would like to offset our power production by about 60% at a minimum.We are as energy efficient as I expect we will ever be at the moment.

Based on PV Watts this system at our location could generate 5,433 kWh per Year - which if I understand the numbers provided by PV Watts - is more than the 60% goal and is more like 80% of last years electrical use. I am OK with that based on the costs.

I do wonder what replacing one of our gas cars with an EV (e.g. low priced used Nissan Leaf) would add to our energy use. We could use the EV as our primary errands/around town car. We only spent $1200 total on gasoline last year for our 2 family cars - so we don't drive a ton, and have little to no commute. I would use the EV to replace an aging 11 year old gasoline car that gets poor sub 20mpg. The EV would account for probably 70% of our future driving needs. And the cost of the car would be offset by the amount we can sell our low mileage 2004 car.

I thought I would post my numbers to see if anyone has any comments on where we are right now - and how my numbers look.

I'm sure others w/ EV's have better information, but I'd SWAG an EV gets about 3 miles/kWh or better in the "mileage" dept. So, 12,000 miles/yr ~~= 4,000 kWh added use. Now, if you read up on how your rates are likely to change, AND you can change over to T.O.U., if not there already, AND if you can charge the EV at super off peak rates, you may be able to get a reasonable dart throw on how/if an EV might affect your most cost effective system size, or what an EV w/T.O.U. would do to your annual bill.

[w00dy]

I'm sure others w/ EV's have better information, but I'd SWAG an EV gets about 3 miles/kWh or better in the "mileage" dept. So, 12,000 miles/yr ~~= 4,000 kWh added use. Now, if you read up on how your rates are likely to change, AND you can change over to T.O.U., if not there already, AND if you can charge the EV at super off peak rates, you may be able to get a reasonable dart throw on how/if an EV might affect your most cost effective system size, or what an EV w/T.O.U. would do to your annual bill.

Thanks for your reply. I don't think we will drive 12,000 miles a year, that is way more than we do - last 11 years 2 cars we are at 74,000 miles. So more like 7k per year total. With 2 cars we think the EV would be about 70% of that use, so 5600 miles for the EV.

So less than 2,000 kWh added????

We could change to T.O.U. but like many families we do have lots of needs right at the tail end of the T.O.U. window for cooking meals and kids being home from school. We could easily push EV charging and domestic use to after hours.

[ZybdZY]

Thanks for your reply. I don't think we will drive 12,000 miles a year, that is way more than we do - last 11 years 2 cars we are at 74,000 miles. So more like 7k per year total. With 2 cars we think the EV would be about 70% of that use, so 5600 miles for the EV.

So less than 2,000 kWh added????

We could change to T.O.U. but like many families we do have lots of needs right at the tail end of the T.O.U. window for cooking meals and kids being home from school. We could easily push EV charging and domestic use to after hours.

The period of the high T.O.U. is also the period for solar generation - so mostly you would be a net producer even with a bit higher usage during the tail end.

Is the price you put in the first post using central inverter ? If so, you may be able to do better than the quote - very likely since you are planning for installation sometimes next year.

[J.P.M.]

Thanks for your reply. I don't think we will drive 12,000 miles a year, that is way more than we do - last 11 years 2 cars we are at 74,000 miles. So more like 7k per year total. With 2 cars we think the EV would be about 70% of that use, so 5600 miles for the EV.

So less than 2,000 kWh added????

We could change to T.O.U. but like many families we do have lots of needs right at the tail end of the T.O.U. window for cooking meals and kids being home from school. We could easily push EV charging and domestic use to after hours.

The 12,000 miles/year was for illustrative purposes only. Your mileage will vary. 5,600 miles/yr. /3miles/kWh ~ = 1,867 kWh/yr. Don't know if you can stay on tiered rate for part of your use and T.O.U. for EV charging. Check w/ your POCO.

[Willaby]

$3.50 per Watt before FTC. I thought I would post my numbers to see if anyone has any comments on where we are right now - and how my numbers look.

That's an excellent price, hopefully from a reputable installer. Based on your numbers you'd be well into tier 1 territory, but since we live in California where even the bottom tiers are higher than the national average, it doesn't hurt to go a little bigger as the return is not bad. From the sound of it, a 15-16 panel system would cover all your current usage, and if on an EV-TOU plan, it would likely cover all of the Leaf kwh especially with the credits. You could ask your installer to add 4 panels and maybe do a little better on his quote too?

Now, some here on the forum might argue with my advice, but know they are the ones who now realize they've came up a little short on capacity and it is difficult for them to admit their shortsighted time horizon. In spite of this no one on the forum has said "gee, darn-it, I wish I had LESS solar", yet there are perhaps one or two who didn't plan well and wish they had more. Think about peak period shifts, degradation, escalating rates, etc, etc and the big ones: end of NEM 1.0 and the FTC(?). It makes a ton of sense to go just a little bigger.

Btw, you're similar to where I was a year ago: a Chevy Volt running 12k miles a year and my house, all now covered by my 4.5kwh system, and I set my thermostat to 76 without worry. Good luck!

[jflorey2]

I'm sure others w/ EV's have better information, but I'd SWAG an EV gets about 3 miles/kWh or better in the "mileage" dept.

We have a Leaf and average about 3.8miles per kwhr. 3 miles per kwhr would be a safe estimate for how much power it will use from an AC charger (taking charging losses into account.)

[w00dy]

The period of the high T.O.U. is also the period for solar generation - so mostly you would be a net producer even with a bit higher usage during the tail end.

Is the price you put in the first post using central inverter ? If so, you may be able to do better than the quote - very likely since you are planning for installation sometimes next year.

Yes forgot about the switch to TOU corresponding to peak generations...whoops that helps a bit.

The price was for micro inverters - when I meet with him I will check on other options/prices.

That's an excellent price, hopefully from a reputable installer. Based on your numbers you'd be well into tier 1 territory, but since we live in California where even the bottom tiers are higher than the national average, it doesn't hurt to go a little bigger as the return is not bad. From the sound of it, a 15-16 panel system would cover all your current usage, and if on an EV-TOU plan, it would likely cover all of the Leaf kwh especially with the credits. You could ask your installer to add 4 panels and maybe do a little better on his quote too?

Now, some here on the forum might argue with my advice, but know they are the ones who now realize they've came up a little short on capacity and it is difficult for them to admit their shortsighted time horizon. In spite of this no one on the forum has said "gee, darn-it, I wish I had LESS solar", yet there are perhaps one or two who didn't plan well and wish they had more. Think about peak period shifts, degradation, escalating rates, etc, etc and the big ones: end of NEM 1.0 and the FTC(?). It makes a ton of sense to go just a little bigger.

Btw, you're similar to where I was a year ago: a Chevy Volt running 12k miles a year and my house, all now covered by my 4.5kwh system, and I set my thermostat to 76 without worry. Good luck!

Thanks for the tips - Seems to be a highly rated installer - - turns out the owner lives near me, should be meeting with him sometime next week. I do have a few questions like cost for going up in size a little - cost for switching from micro inverters to a string inverter - I will see where that puts us.

No thermostat settings at the moment in the summer anyway - might look at getting a Ductless MiniSplit if we find we want some cooling, and to supplement our gas fired radiant heat for the winter...hmm that just adds a bit more to our needs - sigh

We have a Leaf and average about 3.8miles per kwhr. 3 miles per kwhr would be a safe estimate for how much power it will use from an AC charger (taking charging losses into account.)

Thanks for that info - so that would add 16,800 kW per year to our needs?? at 3 miles per kwhr * 5600 miles??

[w00dy]

The 12,000 miles/year was for illustrative purposes only. Your mileage will vary. 5,600 miles/yr. /3miles/kWh ~ = 1,867 kWh/yr. Don't know if you can stay on tiered rate for part of your use and T.O.U. for EV charging. Check w/ your POCO.

There is a PG&E rate for EV and TOU - I will see if that makes it pencil out better - PG&E TOU E6 Rate would supposedly save me money right now according to PG&E - I should probably switch to that rate anyway to make sure I get grandfathered in as they might lock out this rate after Jan 1, 2016.

Here are some interesting screen shots:

My current daily use


Switching to EVA rate (based on last years bills):


Switching to E6 Time-Of-Use Rate (based on last years bills):

[w00dy]

Back to the DIY alternative - as that was my original plan.

I have looked for a long time at going with a package from one of the online companies selling systems for DIY. Doing this would cost me in the neighborhood of $8,000 for materials for a 12 panel system with micro-inverters (trying to compare apples to apples at the moment). Then I would need to pay for my city permit, an electrical contractor to do the hookup. I was figuring around $1K-$2K tops in our area for the electrician. In addition I would have to pay for a Structural Engineer to stamp any plans that I draw up which adds a further few hundred $ more. With that in mind my latest quote is only $1000-1500 more than DIY with certainly less headaches...???

I would love to find a reputable installer who can beat $3.5/w - that will be my goal I think going forward.

[Willaby]

Back to the DIY alternative - as that was my original plan.

I have looked for a long time at going with a package from one of the online companies selling systems for DIY. Doing this would cost me in the neighborhood of $8,000 for materials for a 12 panel system with micro-inverters (trying to compare apples to apples at the moment). Then I would need to pay for my city permit, an electrical contractor to do the hookup. I was figuring around $1K-$2K tops in our area for the electrician. In addition I would have to pay for a Structural Engineer to stamp any plans that I draw up which adds a further few hundred $ more. With that in mind my latest quote is only $1000-1500 more than DIY with certainly less headaches...???

I would love to find a reputable installer who can beat $3.5/w - that will be my goal I think going forward.

You are almost exactly where I was as recently as six months ago, the numbers and system size are almost the same. Electric car, even my panels are 280's, etc. I even had the time to do it DIY. I started at 12 panels, then quoted for 14, but went for 16 @ $3.45/w. The DIY killer for me was my tile roof and the permit process. Like you, I got down to $1500 savings, so just not worth it. All I did myself was run the conduit inside the walls (a must for me).

I would suggest this (and let me know how it goes if you do it): tell your installer you like his quote, but just to add 4 more panels and optimizers would only be an additional materials cost for him of ~$1500, so would he do it for $2000 more. If you do this, all else good, you would be at $3.05. If he countered at $2500 extra, that would be ~$3.20/w and I would say "DEAL". (don't forget the ITC cuts it all down by 30%).

[w00dy]

You are almost exactly where I was as recently as six months ago, the numbers and system size are almost the same. Electric car, even my panels are 280's, etc. I even had the time to do it DIY. I started at 12 panels, then quoted for 14, but went for 16 @ $3.45/w. The DIY killer for me was my tile roof and the permit process. Like you, I got down to $1500 savings, so just not worth it. All I did myself was run the conduit inside the walls (a must for me).

I would suggest this (and let me know how it goes if you do it): tell your installer you like his quote, but just to add 4 more panels and optimizers would only be an additional materials cost for him of ~$1500, so would he do it for $2000 more. If you do this, all else good, you would be at $3.05. If he countered at $2500 extra, that would be ~$3.20/w and I would say "DEAL". (don't forget the ITC cuts it all down by 30%).

Thanks for that advice and relating your experience. I will see what I can do with a few more panels and negotiate a better price by adding them!

We have a pretty good situation in that our roof is a standing seam metal roof - so it is very easy to add panels (no roof penetrations). I think adding 2-4 panels would be pretty easy in our case. I have also already run the major underground conduit to just under the area where the panels will be - the city even inspected it! So that part of the job is already done - I am not sure the installer knows about that or has factored that into his quote!

[ZybdZY]

...

I would love to find a reputable installer who can beat $3.5/w - that will be my goal I think going forward.

Sent you a pm

[Willaby]

Thanks for that advice and relating your experience. I will see what I can do with a few more panels and negotiate a better price by adding them!

We have a pretty good situation in that our roof is a standing seam metal roof - so it is very easy to add panels (no roof penetrations). I think adding 2-4 panels would be pretty easy in our case. I have also already run the major underground conduit to just under the area where the panels will be - the city even inspected it! So that part of the job is already done - I am not sure the installer knows about that or has factored that into his quote!

Of course this is assuming you want 4 more panels, or maybe just 2, but the same logic applies. Definitely ask the installer to factor in the conduit already done.

"so that would add 16,800 kW per year to our needs?? at 3 miles per kwhr * 5600 miles??"

on this one, should be the other way around: 5600 miles would be just 1800 kw/yr, give or take.

[w00dy]

Of course this is assuming you want 4 more panels, or maybe just 2, but the same logic applies. Definitely ask the installer to factor in the conduit already done.

"so that would add 16,800 kW per year to our needs?? at 3 miles per kwhr * 5600 miles??"

on this one, should be the other way around: 5600 miles would be just 1800 kw/yr, give or take.

OK - yes I see my mistake - did the opposite on the equation.

If I go with 4 more panels, according to PVWatts, I would be pretty close to 100% of current use - that is without factoring in an electric vehicle. So depending on the cost upgrade from 12 to 14 or 16 panels I should have a better shot of figuring out the best option.