Not much talk about solar power in SW Florida (sales, leasing)

[MartyGras]

Originally Posted by az99

Knock yourself out with the battery system and let us know how it works out and how much it costs.

For what you will spend on your batteries and cables you can buy a generator capable of supplying more power than you will get conserving your battery power at night or when the sun isn't out.

You will also get to replace the batteries every several years and dedicate a decent size space in your home to store the batteries.
A solar/battery system is for a hunting camp in the middle of nowhere without power.

Tesla just announced their battery system for solar applications..

Powerwall | Tesla Home Battery

[HarborRat]

Originally Posted by MartyGras

Tesla just announced their battery system for solar applications..

Powerwall | Tesla Home Battery

That price doesn't seem too bad....If you are a solar owner and use much of your power at night or are worried about outages it could be worth it. It "might" pay for itself in that time, but even if it doesn't it is good peace of mind.

Like I said before AZ, just because it's not the "norm" doesn't mean it is not needed, or outdated technology, or "only for homes in the boonies". Elon Musk (Tesla CEO, Space X, Paypal, Solarcity etc) thinks outside the box and comes up with solutions for actual problems. No storage capacity on a home solar array IS a problem, big problem. But the solar companies won't tell you that when taking your $30k because they won't profit from it and their price raise would scare off consumers. I think it is idiotic to spend all that money on a solar array and NOT have at least some sort of battery bank to use at night or during an outage.

In one of my first posts I said solar doesn't make sense for me because half the year when the AC is not on the solar would be producing energy I'd never use during the day. A battery bank like this or a much cheaper home made version would solve that, partially.

[az99]

Originally Posted by MartyGras

Tesla just announced their battery system for solar applications..

Powerwall | Tesla Home Battery

That is interesting. That would also work well in an area that has low overnight rates to charge it and use during the day.

[davephan]

The Tesla Energy Powerwall is a way to provide backup power without the problems associated with a standby generator, such as the noise and fuel. Each Powerwall unit is 4 feet x 3 feet x 7 inches, has 10 KWH capacity, costs $3,500, and is designed for backup power use. The Powerwall uses lithium battery technology. They also have a 7 KWH Powerwall stackable unit designed for daily cycling, for use with a PV solar system or with off-peak utility power, and costs $3,000. The wall mounted units and can be horizontally stacked up to 9 units.

The average household uses 30 KWH per day. So, one Powerwall would provide 8 hours of backup power. If the power consumption was reduced, one Powerwall would last longer. Otherwise additional Powerwall units would be needed to provide enough capacity. It all comes down to how much capacity and time duration needs to be covered by the backup power. If outages typically only lasted hours, then the Powerwall might be a good solution to cover the power outages. If the outages didn't last too many hours, then the AC could be kept running during the outage. Outages for days would still require a generator, along with the maintenance, noise, and fuel problems.

The payback time could be 8 1/2 years with the daily cycling if the electricity costs 13 cents per KWH, but in Hawaii, the electricity is very expensive, the payback time is about 3 years. It probably wouldn't be viable to use the battery for using off-peak rates, unless the off-peak rates are very inexpensive.

Elon Musk is building a two billion dollar gigafactory in Nevada to produce the Powerwalls. Since he is building the factory in Nevada, he will creating more American jobs, instead of building the factory overseas. He also open sources the patents like his other companies, so that other companies can freely use the technology. He is hoping that other companies will open their own gigafactories to produce more batteries.

Telsa Energy also makes a business class 100 KWH Powerpack. The 100 KWH Powerpacks can be stacked without limit to beyond 1 gigawatt systems that could power a city. One utility already purchased a 250 megawatt system.

Clearly, Elon Musk is a big thinker who can do things on a massive scale, sees and believes that solar power and batteries is the next big thing in the US and globally. He also thinks that is the solution to solve the global greenhouse gas problem that could threaten life on the planet in the long term.

But for the average person, or perhaps a little above the average income person, the Telsa Energy Powerwall system might good solution to solve the shorter term electric outage problems without the hassles you get using electric generators.

Here's another video that has more information about the Powerwall:

https://www.youtube.com/watch?v=FHswxauDGVg

The blue square in the photo shows the land mass area for PV solar systems to completely eliminate all fossil fuel generated electric power in the US. The red dot inside the blue square shows the land mass for the batteries. Of course, the solar power and batteries would be spread throughout the US.

[Big House]

Interesting. I have a follow up. Here in Florida, battery life is terrible in the heat. I wonder how one of these batteries would hold up, and how long the life of it would be. I think you'd need to mount it in a conditioned space if you want any kind of decent life from it.

And, in the even of a bad hurricane, or storm, you may still need a generator - depends on the condition.

I like the concept. I think that in order to make it efficient, you'd need a group to contribute to the cost and use. I think it could furnish plenty of power, with excess remaining each night (that would be efficient if shared), as would the cost spread over a group using that more efficiently than a singe user. People today are very individualistic. I grew up in a small town where people used to band together to take on projects and share the benefits. That doesn't happen much any more.

[az99]

One other thing is their daily average usage of 30 KWH. I just checked my latest bill. It averaged 46KWH. So over 50% higher than their # and it is not hot yet and we have a small house.
Probably after you buy your Tesla car you would want the power pack just to say you have one.

[HarborRat]

Originally Posted by az99

One other thing is their daily average usage of 30 KWH. I just checked my latest bill. It averaged 46KWH. So over 50% higher than their # and it is not hot yet and we have a small house.
Probably after you buy your Tesla car you would want the power pack just to say you have one.

I averaged 38kw last month. I think this more of a solution to save some of that free solar power for nighttime.

I just checked my FPL "Dashboard" and from 10pm till 7 am I use about 1kw per hour (I sleep with the tv on, and the AC kicks on at least once an hour). So that is 10 hours and the full 10kw. At FPL rates that is about $1 a day savings. At that rate it would take about 9.5 years till ROI is reached. Warranty is 10 years, and I don't expect the batteries to last much longer than that.

This battery won't save you money, but it is a step in the right direction.

[az99]

Another thing with solar,that you probably know, is that with a typical roof mount system you only make your rated max output for a few hours per day. Likely more hours in Fla.. On my system as soon as the sun rises it starts making a small amount of power. But does not make peak power until about 10AM and stays there (assuming clear sky) until about 2PM and then starts decreasing until sunset.
The reason I mention that is you would have to have a solar system that far exceeds your usage at noon with AC load etc. so that it will also charge the fully depleted battery bank. You would probably start pulling on the batteries by 4PM or so.
There are 100 more variables that I am sure you are aware of. Those are what make the grid tie system so popular.

[HarborRat]

Originally Posted by az99

Another thing with solar,that you probably know, is that with a typical roof mount system you only make your rated max output for a few hours per day. Likely more hours in Fla.. On my system as soon as the sun rises it starts making a small amount of power. But does not make peak power until about 10AM and stays there (assuming clear sky) until about 2PM and then starts decreasing until sunset.
The reason I mention that is you would have to have a solar system that far exceeds your usage at noon with AC load etc. so that it will also charge the fully depleted battery bank. You would probably start pulling on the batteries by 4PM or so.
There are 100 more variables that I am sure you are aware of. Those are what make the grid tie system so popular.

I agree with all of that. But this system is designed for a grid-tied system (although can be used off grid too). I assume you could set the time you want this battery to start feeding the grid, which in my case would be 10pm, as it wouldn't last long during the day with the AC running, and won't charge back up for "free" at night.

Off grid systems make sense in the mountains or desert, but for normal homes grid tied is a must. But that does not mean you can't have a hybrid system. When these lithium batteries come down in price, which they will, solar will make more financial sense to me. And when that happens I'll install at least a 10kw system myself for $10k that will have enough extra juice during the day to charge the battery, which will hopefully be larger and much less money than they are currently.

I'll also add that in states that pay you for your extra energy produced at a decent rate it makes less sense to use your extra daytime power to charge a battery. But those credits they promise today could be gone tomorrow.

[Macgregorsailor51]

Its just plain NOT WORTH THE COST in Florida.. As I stated my niece has a system on St Croix.. Since the first month they have been feeding back into the grid almost everyday.. This year their grid credits will be paid back by the power company to help pay off their system.. Electric is now for free and in a few more years providing a storm doesnt destroy it.. They will have a free system and free electric until the system dies a slow natural death..