Considering solar panels, looking for sizing/financing advice

[pdx_m3s]

Our home is all electric, and the family we bought it from was using the fireplace and electric resistive heat to warm the house in the winter, hence the hundred MWh consumed on the meter!

Our next upgrade is a new heat pump to replace the one that's probably 20 years old now. SEER 9, said our HVAC technician. We're hoping once we get a modern heat pump in that can comfortably operate below 32 degrees, our panels will more than cover our annual usage. As it stands now, we're estimating the 12.24 kW system will only cover about 90%.

Even a standard-grade modern heat pump will drastically lower your usage. I think these are around 14-15 SEER. They are efficient to about 35 degrees. After that auxiliary heat may have to kick on, but only for a short time.

I can’t wait to see how our heat pump system works here in the Pacific Northwest. Our only gas appliance is the fireplace. Most people look at us like we’re nuts when we tell them we chose electric over gas equipment throughout the house.

I think we need to rename “natural gas.” It sounds earth friendly, but it’s not. It’s also detrimental to human health. We need to stop burning things. Should be called “gaseous crude oil.”

 

[willow_hiller]

I think we need to rename “natural gas.” It sounds earth friendly, but it’s not. It’s also detrimental to human health. We need to stop burning things. Should be called “gaseous crude oil.”

This just happened in my state a few weeks ago: Baltimore Explosion: BGE Says It's Not At Fault; Fire Officials Continue Investigation In Cause

Honestly I'm glad my neighborhood doesn't have natural gas pipelines. Imagine losing your home or your life because your neighbor had a faulty appliance... I would hope new neighborhoods are being planned without natural gas, but I know it's not the case. A friend of mine is buying a new construction in Rockville and they're having a gas furnace put in for the up-front savings...

 

[BrettS]

I remember when I was a teenager someone smelled gas outside my next door neighbor’s house. Within hours the gas company had heavy equipment there digging up their front yard to find a leaking pipe underground. Luckily no explosion or anything, but it definitely caused some commotion in the neighborhood and it was amazing how quickly they reacted and worked to fix the leak.

 

[jboy210]

Our kWh number will go backwards, but since it started climbing during the month between reset and PTO, and since I don't offset, the numbers are still positive (and I don't know if it actually would go to -1 or all 9's.) Does your meter actually record kWh in and out as two numbers? We only ever get the combined amount.

I don't know about recording a cumulative number. What we see is input number turns negative. It constantly cycles through 4 or 5 values and every time I see the negative energy flow I smile.

 

[BrettS]

I don't know about recording a cumulative number. What we see is input number turns negative. It constantly cycles through 4 or 5 values and every time I see the negative energy flow I smile.

Just how often are you looking at your meter?

 

[jboy210]

Just how often are you looking at your meter?

Every time I walk by it. These days I need something to make me smile!

 

[mpstryker]

My advice on sizing is to install enough solar and powerwall to cover your normal electricity use. In California, at least, the electricity that you generate is worth the full cost of purchasing the same amount (from PG&E, in the north) to the extent that it offsets the purchase. The excess electricity that you sell is worth much less. Every month the kWhs supplied to the grid and taken from the grid are netted out, and you are credited with the difference. Solar plus Powerwall is great because you never buy from the grid at Peak rates (4pm-9pm) but most of what you sell is at Peak rates.

 

[JustSaying55]

If you really want to see a dramatic change in your utility/gas bill then you need to pair all this with a wall battery. I have 2 TESLA s and the savings are dramatic! I’m now an energy arbitrager!

 

[jboy210]

My advice on sizing is to install enough solar and powerwall to cover your normal electricity use. In California, at least, the electricity that you generate is worth the full cost of purchasing the same amount (from PG&E, in the north) to the extent that it offsets the purchase. The excess electricity that you sell is worth much less. Every month the kWhs supplied to the grid and taken from the grid are netted out, and you are credited with the difference. Solar plus Powerwall is great because you never buy from the grid at Peak rates (4pm-9pm) but most of what you sell is at Peak rates.

Do you actually get the peak time of use rate back at true up?

 

[jjrandorin]

My advice on sizing is to install enough solar and powerwall to cover your normal electricity use. In California, at least, the electricity that you generate is worth the full cost of purchasing the same amount (from PG&E, in the north) to the extent that it offsets the purchase. The excess electricity that you sell is worth much less. Every month the kWhs supplied to the grid and taken from the grid are netted out, and you are credited with the difference. Solar plus Powerwall is great because you never buy from the grid at Peak rates (4pm-9pm) but most of what you sell is at Peak rates.

If you are on a time of use plan, thats not quite correct, unless you are somehow generating the majority of your solar power during peak (4-9pm). Thats HIGHLY unlikely though. You get credit for the electricity putting it in the grid at the same price you would be paying at that same time to take it out.

The only "peak" energy credit you would be receiving would be during the TOU time of 4-9pm. During peak solar generation time of 8am to 4pm, you are getting off peak rate credit for solar you put in during that time (which is likely most of it).

 

[jjrandorin]

Do you actually get the peak time of use rate back at true up?

No (well you dont in SCE and I doubt it up there too). You get credit at whatever the rate was when you generated the energy (for most thats off peak rates, but energy you put in from 4-9pm would give peak rate credit... but most people are not generating a ton of solar from 4pm on).

At end of the year true up, if you are a net producer at the end of the year, your credit would be converted to wholesale rates and then paid out. Two years ago (pre model 3 for me) at the end of the year I had $350 ish in NEM credits under my NEM 1.0 with no "non bypassable charges" (with end of year actually being "end of my 12 month net metering period).

The $350 converted to like $47 and they sent me a check for that.

 

[jboy210]

No (well you dont in SCE and I doubt it up there too). You get credit at whatever the rate was when you generated the energy (for most thats off peak rates, but energy you put in from 4-9pm would give peak rate credit... but most people are not generating a ton of solar from 4pm on).

At end of the year true up, if you are a net producer at the end of the year, your credit would be converted to wholesale rates and then paid out. Two years ago (pre model 3 for me) at the end of the year I had $350 ish in NEM credits under my NEM 1.0 with no "non bypassable charges" (with end of year actually being "end of my 12 month net metering period).

The $350 converted to like $47 and they sent me a check for that.

Got it. We are only producing 3 or less kW at 4 PM so I guess we will not expect too much money,

 

[swegman]

I would like to get peoples opinions on an issue I have with a Tesla solar proposal.

For background, I currently own my second model S and a model 3. I am also a Tesla shareholder.

My first model S was delivered with the features that I ordered. My second model S was not. After several discussions with a Tesla, they agreed to retrofit the omitted features. When the model 3 was announced I placed reservations for 2 cars. During discussions with Tesla representatives, I was verbally told the model 3 included an alcatara interior, similar to the model S. When the first model 3 was delivered, it had a cloth headliner instead of the represented alcatara headliner. I was told that a production change resulted in the deletion of the alcatara interior. I accepted the first model 3, decided the cloth headliner cheapened the appearance of the car, and canceled the second model 3.

I am now looking at a solar system and requested a proposal from Tesla. After extensive discussions, we settled on a system with specific components. Upon reviewing the purchase agreement, I noted that it makes absolutely no mention of the equipment to be included or the specific warranty terms for the various components. Further, the agreement provided for execution states that the components may be changed without consent of the purchaser.

The components we agreed to offer, according to verbal and email representations by Tesla project advisors, to have 25 year parts and labor warranty, yet the purchase agreement uses vague and ambiguous (indefinite) language of “at least 12 (10) years. I informed Tesla that I want the purchase agreement to indicate the specific equipment we settled on, for the purchase agreement to specify the warranty is 25 years instead of the indefinite phrase “at least ...”, and that the equipment can only be changed with our approval. They refuse to do say, saying we should trust that they will install the equipment we selected. After prior issues with equipment in the cars being changed without even telling us of the changes, I am not comfortable trusting that no changes will be made. Am I unreasonable to expect that a purchase agreement for a $30K purchase should explicitly list the equipment for the solar system in the purchase agreement, along with the exact warranty term (eg, 25 years)?

Have people here read their purchase agreements before they signed them, and if so, did they specify the specific equipment to be used?

Thanks for your opinions.

 

[Southpasfan]

You have a couple more swings at the components. Before you pay anything other than the $100, they produce detailed plans (just saw mine today) which list all the components for the building permit, in detail. I would get a copy of that because, although its not a conract with you, its an obligation in that Tesla will have to use the components they submit.

Then you have another swing at it the day of installation. That's potentiallly a bit confrontational, but if you read the boards someone said that the day of install they showed up with something wrong and he told them to leave and they did.

Its not really like a car, its like a construction project that you personally oversee.

 

[willow_hiller]

What equipment did you prefer, @swegman ? I like that my system uses Hanwha G6+ 340 watt panels and a SolarEdge SE-11400 inverter, but at the end of the day I've found most panels and equipment in the same price range perform about the same and carry very similar warranties.

Like @Southpasfan said, my layout had the specific equipment detailed on it. And my purchase agreement says "the Contractor shall have the right to substitute System equipment without Customer's agreement, so long as that substitution adds no extra cost to the project and does not materially affect the System's performance." If it doesn't add extra cost, and doesn't affect the system performance, why worry?

 

[swegman]

You have a couple more swings at the components. Before you pay anything other than the $100, they produce detailed plans (just saw mine today) which list all the components for the building permit, in detail. I would get a copy of that because, although its not a conract with you, its an obligation in that Tesla will have to use the components they submit.

Then you have another swing at it the day of installation. That's potentiallly a bit confrontational, but if you read the boards someone said that the day of install they showed up with something wrong and he told them to leave and they did.

Its not really like a car, its like a construction project that you personally oversee.

First swing is no good. They already prepared such drawings bec HOA needs to approve the install. Drawings indicate design is typical and subject to change.

Regarding the second swing, do you really want to get into a confrontation about the equipment on the day of installation?

Lastly, what about the warranty issue? The purchase agreement says the panels are material warranted for “at least 12 years”, the inverter material warranty is for “at least 10 years”, and no mention of any warranty for the power inverters. I tried arguing that the language “at least 12 (10) years” means I can demand warranty coverage 50 years down the road, and it is in their interest to specify an exact time period. They claim not to see a problem.

Regarding the design plans, being an electrical engineer/patent attorney, I reviewed the drawings in detail. Initially the design specified a SE7600 inverter for an 11,560 watt system. When I questioned it, their design department said they can overdrive the inverter by 50%. That is true, but SolarEdge staid that it will only output 7600 watts (the rest going as heat) reducing the point of having an 11,560 watt system. So they changed it to an SE10000 inverter, and after further discussions, to a SE11400 inverter. However, the design shows two arrays totaling 23 panels bring input to a first string input on the inverter, and another array of 11 panels being input to a second string input on the inverter. A third string input on the inverter is shown as not used. The problem is that SolarEdge specifies that each string input is limited to a maximum input of 6000 watts, which is greatly exceeded by the 23 panels. The design department needs to pay better attention when designing a system.

 

[swegman]

What equipment did you prefer, @swegman ? I like that my system uses Hanwha G6+ 340 watt panels and a SolarEdge SE-11400 inverter, but at the end of the day I've found most panels and equipment in the same price range perform about the same and carry very similar warranties.

Like @Southpasfan said, my layout had the specific equipment detailed on it. And my purchase agreement says "the Contractor shall have the right to substitute System equipment without Customer's agreement, so long as that substitution adds no extra cost to the project and does not materially affect the System's performance." If it doesn't add extra cost, and doesn't affect the system performance, why worry?

What equipment did you prefer, @swegman ? I like that my system uses Hanwha G6+ 340 watt panels and a SolarEdge SE-11400 inverter, but at the end of the day I've found most panels and equipment in the same price range perform about the same and carry very similar warranties.

Like @Southpasfan said, my layout had the specific equipment detailed on it. And my purchase agreement says "the Contractor shall have the right to substitute System equipment without Customer's agreement, so long as that substitution adds no extra cost to the project and does not materially affect the System's performance." If it doesn't add extra cost, and doesn't affect the system performance, why worry?

We eventually agreed to use the Hanwha panel with SolarEdge P400 power optimizers and a SolarEdge SE11400 inverter. But they will not list these items in the purchase agreement.

I did suggest making the design plans a part of the agreement if they do not wish to revise the agreement, but they are unwilling to even do that.

The purchase agreement sent to me appears to differ from yours. The agreement I received says the Hanwha panels have at least a 12 year part warranty, whereas they verbally tell me the panel has a 25 year part and labor warranty. The agreement I received does not mention any warranty at all for the power optimizers, but Tesla verbally indicated it is 25 years parts and labor. For the inverter, the agreement indicates it has at least a 10 year part warranty but Tesla verbally told me it has a 12 year part and labor warranty. But again, they will not put this in the purchase agreement.

What section of Maryland are you in? I used to live in Potomac.

 

[BrettS]

I would like to get peoples opinions on an issue I have with a Tesla solar proposal.

Unfortunately Tesla Energy is probably not a good fit as a solar installer for you. Tesla’s approach to solar is to use cookie cutter designs with very little option for changes or customization in order to keep a rock bottom price. This is simply a trade off that’s made to keep the price down. We have seen cases where Tesla will flat out refuse to sell to people who insist on making changes to the contract or fighting against them and unfortunately I think you are probably getting dangerously close to that point. Tesla’s solar offer is more of a “take it or leave it” type approach. It’s very different from the buying a car model where you can select different options.

This is not to say that I don’t think your opinions are right or that wanting specific equipment or specific warranty requirements is bad. All I’m saying is that you probably aren’t going to get that from Tesla. This is a time when working with a local solar installer is probably going to be a much better fit for you and be much less frustrating. A local installer will be able to take the time to customize the system so you get exactly what you want and be able to provide exactly the warranty that you want.

So I think you really need to make a decision. Do you want a solar system from Tesla Energy at what is likely the lowest possible price? If so then you need to accept the fact that you won’t have a lot of say in the equipment or warranties that they provide. Or do you want to be able to specify your equipment and warranty terms? If so, then you need to find another installer who will be happy to work with you to design exactly the system you want, but you will likely pay more for it.

 

[swegman]

Unfortunately Tesla Energy is probably not a good fit as a solar installer for you. Tesla’s approach to solar is to use cookie cutter designs with very little option for changes or customization in order to keep a rock bottom price. This is simply a trade off that’s made to keep the price down. We have seen cases where Tesla will flat out refuse to sell to people who insist on making changes to the contract or fighting against them and unfortunately I think you are probably getting dangerously close to that point. Tesla’s solar offer is more of a “take it or leave it” type approach. It’s very different from the buying a car model where you can select different options.

This is not to say that I don’t think your opinions are right or that wanting specific equipment or specific warranty requirements is bad. All I’m saying is that you probably aren’t going to get that from Tesla. This is a time when working with a local solar installer is probably going to be a much better fit for you and be much less frustrating. A local installer will be able to take the time to customize the system so you get exactly what you want and be able to provide exactly the warranty that you want.

So I think you really need to make a decision. Do you want a solar system from Tesla Energy at what is likely the lowest possible price? If so then you need to accept the fact that you won’t have a lot of say in the equipment or warranties that they provide. Or do you want to be able to specify your equipment and warranty terms? If so, then you need to find another installer who will be happy to work with you to design exactly the system you want, but you will likely pay more for it.

Tesla had no issue with customizing the design to stay under the Tier 1 system for Florida; hence an 11,560 watt design instead of Tesla’s standard 12,xxx watt system.

The problem is they verbally tell you one thing but the purchase agreement says something else (or nothing at all).

Doing solar is not a necessity for me. I bought the cars because of their performance, and not to reduce my reliance on coal and/or oil or whatever the power company uses to generate electricity. Basically, I was talking with a friend about Tesla and I then said I should add a Tesla solar system. I’m not interested in getting solar from another outfit. I am looking at this solely as supporting a company that Is providing me with terrific stock value returns. However, I am very close to giving up on solar.

 

[Southpasfan]

One also has to consider the price differential. I see your point about how the contract is vague, but it seems to me that is no different than many other warranties- most have exceptions - but as BrettS says, happiness is worth something especially at these prices points.

Thanks to your post I re-read all my contracts and the bottom line is that one of my two 7600 inverters, the Gateway, and one of my three powerwalls could fail and I’d still come out ahead of going with another company even if they made me buy them myself. Plus, it simply does not seem to be analogous to cars, much of what Tesla installs is a third party product. The reason to go with Tesla other than price is the powerwall tech.