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Going solar, going solar, going solar


lokisnow

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(Thread title sung to “riding solo” Jason derulo)

so my house is probably going solar because the 30% ARRA subsidy is phasing out after this year and the Tesla power wall subsidy is in the middle of a phase out. We live in California, in a suburb of Los Angeles.

and the price of solar panels has dropped 90% in the last decade, so it’s become much more affordable.

the financing is quite interesting, you finance  70% of the system on a 3-4% loan for a period of 12-20 years, and your monthly payment that was your electric bill basically becomes your solar system bill. The remaining 30% is financed on an 18 month 0% interest loan that you pay off in full when you receive your tax credit the next year.

at the end of the year though settle up with your utility, they credit you for extra power you’ve sent to the grid and charge you for power you’ve taken from the grid.

You can combine storage with solar and it just folds in to the overall package price, which makes it eligible for the 30% tax credit as well, there are cash rebates from the state to further reduce the cost of storage. We are probably going with a Tesla power wall 2. Storage takes you even more off the grid, though enough electricity is not stored to charge a car.

Averaged over a year, we use about 30 kWh of electricity a day (but about 40-50% of that is overnight car charging.) giving us a bill in the non summer months of about $200 per month. Obviously that can go up a lot in the summer with AC usage, peaking in the $350-400 range. If you break down the figures in more detail, our car charging is about 30-40% of our annual usage.

We drive about 1600+ miles electric per month at a cost of about $100 per month so a per mile cost of $0.0625 (this is my high estimate).

but when we go solar we change to a “time of use” fee structure so the cost of overnight car charging would drop by half or more (we could do time of use now but the best way I’ve figured the math is that the rates for day time electricity are high enough that with a working from home situation we would either break even or pay 10-20% more if we switched)

We got a couple bids for solar, one for 24 panels, which would generate enough power to zero out our “annual” usage, this had a final installed cost with everything (24 microinverters etc) of about $24000 or a monthly payment of about $167 over twelve years. But the caveat here is that they are probably overselling us as they’re just bidding on annual electricity usage which doesn’t really account for 30% of our usage being car charging.

we also got a bid for 18 panels with a Tesla power wall 2 at $193 per month over 12 years ($150 / month @ 20 years). And we had them calculate us a bid at 18 panels but no storage which comes to $135/month @ 12 years or $106 / month @20 years.

It’s pretty exciting to be pulling the trigger on solar right now, much more affordable than I ever expected. 

I think we’ll try and get one more bid and also do some more research on panels/inverters as well try to better calculate our exact needs. I’d rather not overbuy too many panels but under buying would also be a mistake. 

Does anyone know of any resource (that isn’t a solar installer/retailer) that helps you calculate your actual panel needs? This seems to be the trickiest area to figure out and my sense is that with panel prices having fallen so fast so much that overbuying is probably a more common mistake in 2019.

Anyone done solar plus electric car charging, hows that impinge on the amount of panels you need? 

How about experience with solar plus storage? My concern would be that if we are sending excess solar power to charge the battery and then using the battery at night (except for car charging) that would greatly reduce the night time electricity we are buying but would also  reduce what we sell back to the grid in the daytime, reducing our credits we accrue in the non summer months. Then when we inevitably go over in the summer because of the AC, we will build up a fairly large electric bill that won’t be offset by enough credits. Or am I just totally off base with that hypothesis?

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I hope people participate in this thread because these are issues I'm interested in.

Sadly, the right wing government elected in this province last year decided solar power subsidies were shit they didn't want or need and they are gone. I am interested in reports on a Tesla power wall. That seems ideal here, and I have been waiting to hear about real life experience ever since the batteries were announced.

I have just contacted a roofer who will give me a quote for a new roof. My little house (the roof is roughly 450 sq ft. I think) has a flat roof. The new roof would add three inches of insulation and have a white coating. The roofer says it won't be perfect, but I will see a big difference in the summer. I'll be getting a quote this week.

Next on my list is solar panels, hoping for a federal program.

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I am interested to hear how it goes. The government here has currently got a several thousand dollar rebate on home battery systems. It's tempting, though I don't think it makes economic sense for us yet.

We had a ~5kW solar system put in a couple years ago, which dropped our power bills from $150-200 a month to averaging around $40. Will pay for itself in 4-5 years. Well worth the investment.

Our next car will at least be a hybrid, if not full electric. Trying to hold off on that for a while though.

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11 hours ago, Fragile Bird said:

I hope people participate in this thread because these are issues I'm interested in.

Sadly, the right wing government elected in this province last year decided solar power subsidies were shit they didn't want or need and they are gone. I am interested in reports on a Tesla power wall. That seems ideal here, and I have been waiting to hear about real life experience ever since the batteries were announced.

I have just contacted a roofer who will give me a quote for a new roof. My little house (the roof is roughly 450 sq ft. I think) has a flat roof. The new roof would add three inches of insulation and have a white coating. The roofer says it won't be perfect, but I will see a big difference in the summer. I'll be getting a quote this week.

Next on my list is solar panels, hoping for a federal program.

One thing that may be of interest I seem to remember if you are buying a new roof then the Tesla solar roof is cheaper than a conventional roof, because the tiles are lighter so the roof itself has less weight. 

Of course this is for a pitched roof, but may be worth looking into.

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3 minutes ago, Pebble said:

One thing that may be of interest I seem to remember if you are buying a new roof then the Tesla solar roof is cheaper than a conventional roof, because the tiles are lighter so the roof itself has less weight. 

Of course this is for a pitched roof, but may be worth looking into.

Would love to do that, but I don't think I'd be allowed by the muncipality. 

Thing is, our house is old (built 1896) and registered in the national database as "interesting" or whatever the category is. So we have to apply for any and all changes which changes the apperance of the house (not if we choose to change it back to original, however, we are free to do that). I think that roof tiles also count. However, I would love to change to a solar roof, even here in rather rainy Norway.

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2 hours ago, Pebble said:

One thing that may be of interest I seem to remember if you are buying a new roof then the Tesla solar roof is cheaper than a conventional roof, because the tiles are lighter so the roof itself has less weight. 

Of course this is for a pitched roof, but may be worth looking into.

There hasn’t been a single Tesla roof installed in Canada yet, but the website Tesla Canada will take your money for tile orders. The price might be $22 per sq. Ft. Cdn, so a 450 sq. ft. roof is $10,000 for material alone. I have a small addition on the back of the house that has a pitched roof, and I daydream about Tesla tile for it, sometime in the future, connected to a power wall battery in the basement below.

Tesla brags their warranty is for the life of the house or infinity, whichever comes first. That kind of bragging is just stupid. I foresee bankruptcy for that division in the future.

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19 minutes ago, Fragile Bird said:

There hasn’t been a single Tesla roof installed in Canada yet, but the website Tesla Canada will take your money for tile orders. The price might be $22 per sq. Ft. Cdn, so a 450 sq. ft. roof is $10,000 for material alone. I have a small addition on the back of the house that has a pitched roof, and I daydream about Tesla tile for it, sometime in the future, connected to a power wall battery in the basement below.

Tesla brags their warranty is for the life of the house or infinity, whichever comes first. That kind of bragging is just stupid. I foresee bankruptcy for that division in the future.

Roof guarantees are all BS, they typically only replace material costs.  

And yeah Tesla's solar stuff is tanking and they don't seem too interested in devoting more resources towards it right now.

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Iirc the massive increase in complexity makes the roof tiles incredibly difficult. By which I mean it’s effectively thousands of panels to wire up, and not sure I’m remembering but I think on sq cm basis, Tesla tiles are not as efficient as a traditional panel, so a fully tiled roof may not even collect as much energy as a typical roof panel installation.

plus they’re having manufacturing difficulties making a new product from scratch which has prevented them from scaling up.

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We're planning on getting solar this year before the energy credits get scaled back.  The problem is that we love the trees in our yard, and our house is east/west facing, so we're not a great fit for solar panels.  We're probably just going to get a smallish array (5 KW or so) in the part of the roof that gets the best sun (still not great).  That won't cover our full household consumption, but it should cut it down by more than half, possibly a lot more.  We'll see. 

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1 hour ago, Tywin et al. said:

A BIRD!, promoting solar energy over wind? Seems eerily suspicious!

Some months ago an article popped up on Facebook, maybe from Ifuckinglikescience, about a solar windmill design project at a university, or maybe a competition. The goal was to design a super efficient rooftop windmill. The designs were incredible, and compact. I hope that one day one of the designs will show up for sale. The one I really liked looked like a cylinder about 3 or 4 feet tall, maybe 20 inches across, with spiral blades inside. It could produce a lot of power when in action.

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42 minutes ago, Fragile Bird said:

Some months ago an article popped up on Facebook, maybe from Ifuckinglikescience, about a solar windmill design project at a university, or maybe a competition. The goal was to design a super efficient rooftop windmill. The designs were incredible, and compact. I hope that one day one of the designs will show up for sale. The one I really liked looked like a cylinder about 3 or 4 feet tall, maybe 20 inches across, with spiral blades inside. It could produce a lot of power when in action.

I think you took that too seriously. I was just joking about birds getting caught in windmills.

But if we’re talking alternative energy sources, why doesn’t geothermal get more attention? It seems like the most practical way to begin.

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Even here in Alaska, the solar panel booths at home shows and energy fairs draw substantial crowds.  Several people on my route power their houses via wind and solar (at least most of the time).  I see solar panel kits for charging batteries on sale at Home Depot,  intended for boats and campers.

 

Mostly, though, its a snowbird thing here though: people who come here during the summer (land of the midnight sun) for fishing and whatnot, so instead of paying the local utility to run power polls to their cabins they throw up a few solar panels instead.  

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No point in looking into the Tesla roof because our roof is in excellent shape and  I have no desire to replace our roof with a product that doesn’t exist on the open market and if it did exist would cost many times more than a panel solar system that produces more solar energy than the Tesla roof.

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We've had a large array at our lake home/property since 2012.  We power 5 other homes plus ours, and could still put energy back into the Provincial grid here if we wanted to.  This is a ground based system though, I haven't looked into a roof based system (yet), might do so in the future for our in city properties.

https://imgur.com/cqL3Cq1

https://imgur.com/jMYrvtn

 

 

 

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and for those curious we are going with a 24 panel setup (8KW, generates 6.8KW usable AC power (conservatively estimated at), 12,000 kw/yr, which assumes a peak daily production of 4-5 hours per day) plus tesla power wall 2 financed 70/30, @ fixed 3.99% for 20 years for a monthly payment of $179.

our electricity will switch to time of use, and we don't have any electric bill per month (other than some connection fees), cost for any electric usage we have over what we produce/sell back is tallied once per year. But, the powerwall will eliminate most off peak usage, and peak sun time will result in selling back a lot of power to grid for which we will be credited. we should have more than enough credits to (more than) zero out our entire electric usage, including the cost of fueling the electric car.

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Really interesting topic.  If we had a single family house then I would be looking closely at this, but our high rise condo is not suitable.

What about the risk of future changes by the electric utility?  In some states with high adoption of solar panels, the electric utility changed the terms at which they would credit electricity received from private households.  Their problem is that they have a fixed cost of maintaining the power grid and maintaining electricity supply on-demand, but more households were reducing their expenditure and free-riding on the cost of grid maintenance.  So the utility wanted to reduce the credits or else charge a fixed access fee to be on the grid.

This made it less attractive to install solar panels, and was a problem for some households who had already invested in doing so on the assumption that the economic relationship with the electric utility would continue unchanged.

I think some of the states who initially had a problem with this have since been working on a solution so that they are still in aggregate encouraging solar adoption.  Here's an old article about this.  Hopefully the situation has improved since.  Consumer Reports article 2016

Anyway, it creates another variable to keep in mind.

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5 hours ago, lokisnow said:

https://www.cnbc.com/2019/05/09/solar-installations-in-us-exceed-2-million-and-could-double-by-2023.html

More than 2 million american homes now have solar, expected to double again in a few years.

that pace is far to slow, but it's nice to know the number we're at now. 

 

I find that low level of uptake to be completely nuts. I had no idea. Australia, a country with less than 1/10th the US population surpassed 2 million residential installations last year. Currently on 20% of households with solar power.

 

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