Tesla to start making Batteries for Home Solar

Questions on how we spend our money and our time - consumer goods and services, home and vehicle, leisure and recreational activities
stev
Posts: 61
Joined: Wed May 09, 2012 12:21 am
Location: Northern CA, near OR border

Tesla to start making Batteries for Home Solar

Post by stev » Tue Mar 31, 2015 11:12 am

A ‘major’ new Tesla product will be unveiled next month… and it won’t be a car

http://news.yahoo.com/major-tesla-produ ... AAKmAnnIlQ

I read a story somewhere, that a guy bought a wrecked Telsa just for the batteries to use at his solar powered home.

Gropes & Ray
Posts: 1067
Joined: Wed Jul 16, 2014 7:28 am

Re: Tesla to start making Batteries for Home Solar

Post by Gropes & Ray » Tue Mar 31, 2015 12:28 pm

I was surprised to see the bump in their stock when it was relatively well known that they were looking to market battery technology outside of cars. I am skeptical that very many people will purchase a battery for their home.

thenextguy
Posts: 389
Joined: Wed Mar 25, 2009 12:58 am

Re: Tesla to start making Batteries for Home Solar

Post by thenextguy » Tue Mar 31, 2015 1:41 pm

They'll probably end up leasing them, just like they're doing with Solar Panels. I think lots of people would want them. Seems like a no brainer if there are no up front costs and it's cheaper than grid electricity.

itstoomuch
Posts: 5343
Joined: Mon Dec 15, 2014 12:17 pm
Location: midValley OR

Re: Tesla to start making Batteries for Home Solar

Post by itstoomuch » Tue Mar 31, 2015 1:44 pm

Long known outcome.
A problem with renewables is that when the sun doesn't shine or the water does run or wind doesn't blow there is no generation. And when the sun shines, water runs, and wind blows you may not need the power.
Distributive power is strategically necessary.
Rev012718; 4 Incm stream buckets: SS+pension; dfr'd GLWB VA & FI anntys, by time & $$ laddered; Discretionary; Rentals. LTCi. Own, not asset. Tax TBT%. Early SS. FundRatio (FR) >1.1 67/70yo

User avatar
tc101
Posts: 2975
Joined: Tue Feb 20, 2007 3:18 pm
Location: Atlanta - Retired in 2004 at age 54

Re: Tesla to start making Batteries for Home Solar

Post by tc101 » Tue Mar 31, 2015 1:50 pm

A problem with renewables is that when the sun doesn't shine or the water does run or wind doesn't blow there is no generation. And when the sun shines, water runs, and wind blows you may not need the power.
Right. So if we have better batteries to store power when its generated and then use it when it's needed, all this changes.
. | The most important thing you should know about me is that I am not an expert.

hicabob
Posts: 2644
Joined: Fri May 27, 2011 5:35 pm
Location: cruz

Re: Tesla to start making Batteries for Home Solar

Post by hicabob » Tue Mar 31, 2015 2:05 pm

I wonder how the efficiency, longevity and cost will compare with regenerative fuel cells which use excess power for electrolysis to generate hydrogen from water for fuel cell fuel?

http://en.wikipedia.org/wiki/Regenerative_fuel_cell

User avatar
knpstr
Posts: 1882
Joined: Thu Nov 20, 2014 8:57 pm
Location: Michigan

Re: Tesla to start making Batteries for Home Solar

Post by knpstr » Tue Mar 31, 2015 2:52 pm

Gropes & Ray wrote:I am skeptical that very many people will purchase a battery for their home.
People said this about computers too. The battery for the home is the answer to "leveling out" renewable energy collection spikes/droughts. Instead of pumping excess into the grid, store for "when the sun don't shine".
Very little is needed to make a happy life; it is all within yourself, in your way of thinking. -Marcus Aurelius

bhsince87
Posts: 1578
Joined: Thu Oct 03, 2013 1:08 pm

Re: Tesla to start making Batteries for Home Solar

Post by bhsince87 » Tue Mar 31, 2015 2:54 pm

I've always thought a full house battery back up system (think mega UPS) would be nice. I specced-out building one based on lead acid batteries. But it would have been big and expensive. But something based on lithium batteries could make a lot of sense

Even without solar or wind generation, it could have benefits should as load shifting (charge it up on cheap rates, discharge when rates are higher). I'm sure the power companies would like to have those as an option for load shifting during peak hours.

Of course, it would be simple to add some solar capacity. It wouldn't necessarily need to be enough to go totally off grid, but just enough to top off the batteries, and work as a supplement to grid power, but not a complete replacement.

Such a pack could also be nice used in conjunction with a small generator. The generator could keep it charged up and support base load, maybe just during the day or night, and the battery could act as a buffer to cover surge demands.

Make it swappable with the Tesla car battery packs, and it could be even more convenient.
BH87

User avatar
TomatoTomahto
Posts: 7232
Joined: Mon Apr 11, 2011 1:48 pm

Re: Tesla to start making Batteries for Home Solar

Post by TomatoTomahto » Tue Mar 31, 2015 2:59 pm

Gropes & Ray wrote:I was surprised to see the bump in their stock when it was relatively well known that they were looking to market battery technology outside of cars. I am skeptical that very many people will purchase a battery for their home.
In the early 1940s, IBM's president, Thomas J Watson, reputedly said: "I think there is a world market for about five computers."
You might be in good company with an overly pessimistic prediction.

thenextguy
Posts: 389
Joined: Wed Mar 25, 2009 12:58 am

Re: Tesla to start making Batteries for Home Solar

Post by thenextguy » Tue Mar 31, 2015 3:44 pm

TomatoTomahto wrote:
Gropes & Ray wrote:I was surprised to see the bump in their stock when it was relatively well known that they were looking to market battery technology outside of cars. I am skeptical that very many people will purchase a battery for their home.
In the early 1940s, IBM's president, Thomas J Watson, reputedly said: "I think there is a world market for about five computers."
You might be in good company with an overly pessimistic prediction.

The sun is a fad.

Gropes & Ray
Posts: 1067
Joined: Wed Jul 16, 2014 7:28 am

Re: Tesla to start making Batteries for Home Solar

Post by Gropes & Ray » Tue Mar 31, 2015 3:49 pm

TomatoTomahto wrote:
Gropes & Ray wrote:I was surprised to see the bump in their stock when it was relatively well known that they were looking to market battery technology outside of cars. I am skeptical that very many people will purchase a battery for their home.
In the early 1940s, IBM's president, Thomas J Watson, reputedly said: "I think there is a world market for about five computers."
You might be in good company with an overly pessimistic prediction.
I predict they will sell more than 5.

TimDex
Posts: 909
Joined: Mon Feb 19, 2007 5:27 pm

Re: Tesla to start making Batteries for Home Solar

Post by TimDex » Tue Mar 31, 2015 3:59 pm

Batteries are the downfall of home solar systems. They are extremely expensive to obtain a power company equivalent energy source. I would recommend anyone Interested in home solar systems and battery backups visit solarpaneltalk.com and study the various stickies. There are a bunch of electrical engineers over there who are pretty down to earth. Tim
"All man's miseries derive from not being able to sit quietly in a room alone. " -- Pascal

User avatar
Epsilon Delta
Posts: 7318
Joined: Thu Apr 28, 2011 7:00 pm

Re: Tesla to start making Batteries for Home Solar

Post by Epsilon Delta » Tue Mar 31, 2015 5:00 pm

tc101 wrote:
A problem with renewables is that when the sun doesn't shine or the water does run or wind doesn't blow there is no generation. And when the sun shines, water runs, and wind blows you may not need the power.
Right. So if we have better batteries to store power when its generated and then use it when it's needed, all this changes.
But the problem is not unique to renewables. Storage is useful with nukes, coal and gas, since it shifts peak loads to base loads. Utilities have been running pump storage for decades. The issue I see is that if batteries are economic a profit maximizing utility will be all over them. Given the economies of scale, and various control issues I'd expect batteries to be economic for utilities at a higher price than for home owners. So cheaper batteries are good, but for now they are good for people who are off grid for geographical or political reasons, rather than economically motivated homeowners.

kolea
Posts: 1234
Joined: Fri Jul 11, 2014 5:30 pm
Location: Maui and Columbia River Gorge

Re: Tesla to start making Batteries for Home Solar

Post by kolea » Tue Mar 31, 2015 8:49 pm

Why not just use the grid? During the day when the sun is out, sell your PV power to the local utility company, and then after dark you buy it back, or at least buy back some of it. They are the battery. It is silly for everyone to have their own home batteries. There are variations on this system in place in many parts of the country. Some utilities won't buy all the excess power you generate but do not use (like our local utility) but most will store it for you.
Kolea (pron. ko-lay-uh). Golden plover.

bhsince87
Posts: 1578
Joined: Thu Oct 03, 2013 1:08 pm

Re: Tesla to start making Batteries for Home Solar

Post by bhsince87 » Tue Mar 31, 2015 9:46 pm

TwoByFour wrote:Why not just use the grid? During the day when the sun is out, sell your PV power to the local utility company, and then after dark you buy it back, or at least buy back some of it. They are the battery. It is silly for everyone to have their own home batteries. There are variations on this system in place in many parts of the country. Some utilities won't buy all the excess power you generate but do not use (like our local utility) but most will store it for you.
Because around here, power from the grid goes out a lot. And usually, it's only for 2-4 hours at a time. Occasionally for a day or so. Many people have generators, but they're overkill for what we usually need.
BH87

kolea
Posts: 1234
Joined: Fri Jul 11, 2014 5:30 pm
Location: Maui and Columbia River Gorge

Re: Tesla to start making Batteries for Home Solar

Post by kolea » Tue Mar 31, 2015 11:03 pm

bhsince87 wrote: Because around here, power from the grid goes out a lot. And usually, it's only for 2-4 hours at a time. Occasionally for a day or so. Many people have generators, but they're overkill for what we usually need.
I lived in a very rural area where the power would go out, but that would be like 3-4 hours, once a year, in the winter, due to ice storms, in which case there would be about zero PV power being generated anyway. I would say that 99% of the US is on a pretty reliable grid. If Elon Musk is cooking up something, I doubt he is targeting the 1% that have no reliable grid. More likely he is trying to drive up the price of TSLA.
Kolea (pron. ko-lay-uh). Golden plover.

madbrain
Posts: 4896
Joined: Thu Jun 09, 2011 5:06 pm
Location: San Jose, California

Re: Tesla to start making Batteries for Home Solar

Post by madbrain » Tue Mar 31, 2015 11:25 pm

TwoByFour wrote:Why not just use the grid? During the day when the sun is out, sell your PV power to the local utility company, and then after dark you buy it back, or at least buy back some of it. They are the battery. It is silly for everyone to have their own home batteries. There are variations on this system in place in many parts of the country. Some utilities won't buy all the excess power you generate but do not use (like our local utility) but most will store it for you.
Agree. I have a grid-tied solar system in a very large house.
A few years ago, in December, we had a very high amount of rain, and thus very low solar production, which is already usually low in the winter. I still had a very large electric bill that month - which was fortunately offset by the negative bills for most of the other months of the year.

I did the math on the amount and cost of the batteries I would have needed if I had wanted to be completely off-grid that month of December with the same net consumption, without blacking out.
My calculations came to a total battery cost of a minimum $500,000, using the best price I could find on per kWh . I ran it by a few people who vetted it. The corresponding net consumption strictly from the grid would be $5000 a year, so the batteries would have cost the equivalent of 100 years of my power consumption. But of course, batteries don't last anywhere near that long. You would be extremely lucky to get 25 years. 10 are probably more typical.
And of course this cost wouldn't include any required generator - such as solar panels - but those would be only a tiny fraction of $500k.

The whole thing was just completely impractical. At that price, it would be very much like Thomas Watson's computer, anyway. I didn't even bother calculating the volume the batteries would take - they probably wouldn't fit in my garage and would have needed construction of a separate building to store them.

What would make sense however, is to have a small battery system, grid-tied, used for power shifting. Ie. on those rainy days, during daytime, when I'm not home, the battery can drain itself and sell power to the grid, so you can get compensated for selling that electricity at peak rates. Meanwhile, you recharge the battery at night at low rates.
Even if you have zero net consumption from the battery charging/discharging, this power shifting will earn you a credit that you can use towards your actual electrical consumption from the grid at other hours. I am guessing this is the sort of system that will be announced by Tesla.
This would present an interesting installation problem, though. In grid tied systems, the local utility requires onsite generators - such as solar and wind generators - to be disconnected from the grid, if the grid goes down. This is supposedly for safety reasons, to avoid harming utility service personnel when they are restoring power to the grid. Presumably the same restriction would apply to a grid-tied battery power shifting system. Thus, such a system could only be used for power-shifting, but not for backup if the grid goes down, unless somehow there is some magic device that can isolate the battery generator and disconnect the house from the grid while the grid is down. I'm not an EE so I don't know if such a device exists or what it would be called.

User avatar
HomerJ
Posts: 11044
Joined: Fri Jun 06, 2008 12:50 pm

Re: Tesla to start making Batteries for Home Solar

Post by HomerJ » Tue Mar 31, 2015 11:28 pm

bhsince87 wrote:Because around here, power from the grid goes out a lot. And usually, it's only for 2-4 hours at a time. Occasionally for a day or so. Many people have generators, but they're overkill for what we usually need.
Where do you live?

Valuethinker
Posts: 34680
Joined: Fri May 11, 2007 11:07 am

Re: Tesla to start making Batteries for Home Solar

Post by Valuethinker » Wed Apr 01, 2015 3:53 am

There are some points that need to be made here:

- the US is not the world. In Emerging Markets, grid failure is a constant problem so backup batteries work especially well with solar (the alternative is diesel fueled generators, and diesel can have a very high cost in rural Africa or Asia or LatAm).

- electricity is much more valuable at certain times of day. The obvious business model is that you lease your battery pack and in return leasing co can sell power to electric utility at peak times. Now in much of the USA, you have a summer peak around 4-6pm ie solar power on an angled panel is good. However you also have morning spikes and you have winter spikes around 4.30-7.30 -- no sun.

- N Am houses are big by world standards, and so there is room for this sort of thing.

Although the need for the average NAm homeowner to have a large battery pack is limited there are probably 1% who could use this, and if you add in the possibility of selling power back to the grid at peak times, this number could be several times larger.

Just like the Tesla itself the obvious market is small, but once you throw in utility finance of these things (leasing, generally) it could get a lot bigger. And in the long run as battery prices fall it could almost become a standard in new homes (talking probably 20 years out).

Valuethinker
Posts: 34680
Joined: Fri May 11, 2007 11:07 am

Re: Tesla to start making Batteries for Home Solar

Post by Valuethinker » Wed Apr 01, 2015 4:13 am

TwoByFour wrote:
bhsince87 wrote: Because around here, power from the grid goes out a lot. And usually, it's only for 2-4 hours at a time. Occasionally for a day or so. Many people have generators, but they're overkill for what we usually need.
I lived in a very rural area where the power would go out, but that would be like 3-4 hours, once a year, in the winter, due to ice storms, in which case there would be about zero PV power being generated anyway. I would say that 99% of the US is on a pretty reliable grid. If Elon Musk is cooking up something, I doubt he is targeting the 1% that have no reliable grid. More likely he is trying to drive up the price of TSLA.
He has a solar company and an electric car company. This is the bridge. If he has too many batteries from his new battery plant, he's just given himself a market.

As I say perhaps 1% (less?) of North American households are natural markets for this. Add in though emerging markets (probably 1% of all EM households have backup generators, and diesel fuel *costs*-- places like Iraq it will be more like 10%) and you are talking some pretty big end user markets.

If I was a utility I wouldn't be worrying about the short term impact of this *but* 20 years out (and utilities have to think 20-30 years out) this could get to be a serious factor.

Call_Me_Op
Posts: 6793
Joined: Mon Sep 07, 2009 2:57 pm
Location: Milky Way

Re: Tesla to start making Batteries for Home Solar

Post by Call_Me_Op » Wed Apr 01, 2015 5:34 am

I don't think you need solar for these batteries to be useful. I think the best application would be to replace back-up generators.
Best regards, -Op | | "In the middle of difficulty lies opportunity." Einstein

User avatar
happymob
Posts: 542
Joined: Wed Nov 18, 2009 4:09 pm

Re: Tesla to start making Batteries for Home Solar

Post by happymob » Wed Apr 01, 2015 6:39 am

TwoByFour wrote:Why not just use the grid? During the day when the sun is out, sell your PV power to the local utility company, and then after dark you buy it back, or at least buy back some of it. They are the battery. It is silly for everyone to have their own home batteries. There are variations on this system in place in many parts of the country. Some utilities won't buy all the excess power you generate but do not use (like our local utility) but most will store it for you.
Not all states have generous net metering requirements. Some states others only require that the utility pay wholesale rates, rather than full retail.

Valuethinker
Posts: 34680
Joined: Fri May 11, 2007 11:07 am

Re: Tesla to start making Batteries for Home Solar

Post by Valuethinker » Wed Apr 01, 2015 7:23 am

It's worth adding there is another natural market.

The US military. Due to the energy requirements of the high tech US approach to warfare, the US has a problem with operational mobility. It can take 10 gallons of aviation kerosene to get 1 gallon of diesel fuel to a front line base. And of course diesel generators are noisy and require maintenance as well as reduce security (easy target, noise impairs protection and reveals location etc.).

They are presumably already well down this path (particularly the USMC which does a lot of the 'thinking' about warfare that the larger services often lag behind on eg issues like low intensity warfare, urban warfare etc.) but cheaper battery packs would couple well with solar panels for base use.

Add in military, emergency services, park rangers etc. and you will get to a significant specialized market. Doubtless a Value Added Reseller (VAR) channel will quickly emerge once Musk is go-to-market with this.

MildlyEccentric
Posts: 65
Joined: Mon Mar 10, 2014 9:28 am

Re: Tesla to start making Batteries for Home Solar

Post by MildlyEccentric » Wed Apr 01, 2015 7:51 am

I did the math on the amount and cost of the batteries I would have needed if I had wanted to be completely off-grid that month of December with the same net consumption, without blacking out.
My calculations came to a total battery cost of a minimum $500,000, using the best price I could find on per kWh .
Wow, that's a lot of batteries! In the commercial world, you would typically equip enough batteries to let you operate during a short power outage combined with a failover to a generator if an outage lasted for an extended period. As you illustrate, it's not economical to operate for long intervals from batteries only.

User avatar
magellan
Posts: 3469
Joined: Fri Mar 09, 2007 4:12 pm

Re: Tesla to start making Batteries for Home Solar

Post by magellan » Wed Apr 01, 2015 8:06 am

IMO, positioning this with solar is exactly backwards, at least in the industrialized world. The business case for something like this is to charge the batteries overnight using cheap underutilized grid power. Overnight, spot prices for electricity can be 1/5 to 1/10th of peak prices because the grid is so underutilized at night.

The next day, with the batteries fully charged, power can be sold back to the utility during peak usage times for top dollar. This type of time arbitrage could create economic value by smoothing out demand on the grid and eliminating the need for expensive new generation and transmission capacity that will only be utilized part-time. The big question is whether the economics of using battery systems will be better than using generation and transmission capacity part-time.

Distributing the batteries throughout the grid, close to where power will be used, helps with efficiency because in many areas, transmission lines to move electricity from power plants to users is as much of a capacity bottleneck as the powerplants themselves.

lightheir
Posts: 2250
Joined: Mon Oct 03, 2011 11:43 pm

Re: Tesla to start making Batteries for Home Solar

Post by lightheir » Wed Apr 01, 2015 8:27 am

Selling back to the grid is the best solution for now, but given solar's continued and progressive rise, we will soon reach the tipping point where utilities will no longer permit sellback of surplus energy to the grid, or at least hugely reduce the fees paid to sell back such energy.

Some countries with strong solar industries are already noting that the impact of solar is already a real economic threat to their established fossil fuel industries. It's not that they're trying to preserve the jobs in these polluting fossil fuel plants - they'd love to get rid of them entirely. But fact remains that until you can have a reliable source of off-peak power, you are still heavily reliant on those fossil fuel industries, and if solar near-bankrupts them will surplus peak energy sellback, they'll have to eliminate the sellback.

Obviously, batteries (if done correctly) can potentially alleviate this future situation, and given the incredible rate of solar (esp compared to the fossil fuels), it looks like whomever is first to achieve a working (not perfect, but working) solution on a large scale will be a huge player in the industry.

Valuethinker
Posts: 34680
Joined: Fri May 11, 2007 11:07 am

Re: Tesla to start making Batteries for Home Solar

Post by Valuethinker » Wed Apr 01, 2015 9:25 am

lightheir wrote:Selling back to the grid is the best solution for now, but given solar's continued and progressive rise, we will soon reach the tipping point where utilities will no longer permit sellback of surplus energy to the grid, or at least hugely reduce the fees paid to sell back such energy.

Some countries with strong solar industries are already noting that the impact of solar is already a real economic threat to their established fossil fuel industries. It's not that they're trying to preserve the jobs in these polluting fossil fuel plants - they'd love to get rid of them entirely. But fact remains that until you can have a reliable source of off-peak power, you are still heavily reliant on those fossil fuel industries, and if solar near-bankrupts them will surplus peak energy sellback, they'll have to eliminate the sellback.
A related problem is that the distribution grid was not built to take lots of power coming from distributed nodes. This is becoming an issue which will necessitate heavy investment.

On the fossil fuel plants, many (most?) grids now have a 'capacity payment' system which allows utilities to 'bid in' capacity that will only be needed at times of peak demand (ie less than 1000 hours pa, or even less). PJM (Mid Atlantic) certainly does, and the UK National Grid now has such a system.

Keeping a lot of gas turbines (that already exist) idle is actually not that expensive, given that they were only ever intended to run at peak times. When we get to mid merit load and the big coal plants and combined cycle gas turbines, that's more of an issue-- how to set the capacity payment to keep those plants available, even if not often used. And when those plants are replaced.
Obviously, batteries (if done correctly) can potentially alleviate this future situation, and given the incredible rate of solar (esp compared to the fossil fuels), it looks like whomever is first to achieve a working (not perfect, but working) solution on a large scale will be a huge player in the industry.
It's very much like what has happened to telecoms in the last 40 years, and if you remember the legal fights to get MCI & Sprint established (the first Long Distance competitors to AT&T) and then the AT&T breakup you can see that the incumbents will fight back fiercely.

The inability to store electricity en masse (except by pumped hydro storage) is the greatest problem with electricity and makes it somewhat unique amongst commodities for that reason.

Valuethinker
Posts: 34680
Joined: Fri May 11, 2007 11:07 am

Re: Tesla to start making Batteries for Home Solar

Post by Valuethinker » Wed Apr 01, 2015 9:27 am

magellan wrote:IMO, positioning this with solar is exactly backwards, at least in the industrialized world. The business case for something like this is to charge the batteries overnight using cheap underutilized grid power. Overnight, spot prices for electricity can be 1/5 to 1/10th of peak prices because the grid is so underutilized at night.

The next day, with the batteries fully charged, power can be sold back to the utility during peak usage times for top dollar. This type of time arbitrage could create economic value by smoothing out demand on the grid and eliminating the need for expensive new generation and transmission capacity that will only be utilized part-time. The big question is whether the economics of using battery systems will be better than using generation and transmission capacity part-time.

Distributing the batteries throughout the grid, close to where power will be used, helps with efficiency because in many areas, transmission lines to move electricity from power plants to users is as much of a capacity bottleneck as the powerplants themselves.
It's a good analysis. Remains to be seen if Musk has really 'cracked it' given the scale we are talking.

However my guess is at least 1% of US households might have other reasons to do this as well: frequent power outages etc. At which point, a lease payment from the utility for the additional storage capacity could turn into something quite valuable (effectively allowing the powerpack to be highly subsidized, or even free).

User avatar
Epsilon Delta
Posts: 7318
Joined: Thu Apr 28, 2011 7:00 pm

Re: Tesla to start making Batteries for Home Solar

Post by Epsilon Delta » Wed Apr 01, 2015 9:42 am

TwoByFour wrote:If Elon Musk is cooking up something, I doubt he is targeting the 1% that have no reliable grid. More likely he is trying to drive up the price of TSLA.
That's exactly what he did with the Tesla S. 3 million customers in the US or 70 million globally is plenty of business.

User avatar
Epsilon Delta
Posts: 7318
Joined: Thu Apr 28, 2011 7:00 pm

Re: Tesla to start making Batteries for Home Solar

Post by Epsilon Delta » Wed Apr 01, 2015 9:57 am

Valuethinker wrote:
magellan wrote: Distributing the batteries throughout the grid, close to where power will be used, helps with efficiency because in many areas, transmission lines to move electricity from power plants to users is as much of a capacity bottleneck as the powerplants themselves.
It's a good analysis. Remains to be seen if Musk has really 'cracked it' given the scale we are talking.

However my guess is at least 1% of US households might have other reasons to do this as well: frequent power outages etc. At which point, a lease payment from the utility for the additional storage capacity could turn into something quite valuable (effectively allowing the powerpack to be highly subsidized, or even free).
I agree with the engineering, but I believe in economies of scale. It will make economic sense for the utility, or a commercial service, at substations before it makes sense at individual homes. And for people who go on about the magic of the market, the utility knows the price in real time at least as well as you do. Residential time of use rates are currently vague approximations that will result in inefficient operations.

As for using batteries both for a backup and for grid balancing. Not a good idea. The utility will suck them dry just before the grid goes down. If you want reliability you need the backup to be sitting around not doing anything.

jimbowman
Posts: 33
Joined: Mon Oct 13, 2014 11:53 pm

Re: Tesla to start making Batteries for Home Solar

Post by jimbowman » Wed Apr 01, 2015 9:58 am

I know Solar City and them had to stop their initial pilot program in California because the power companies were intentionally delaying hooking them up or outright refusing to.

musbane
Posts: 390
Joined: Sun Oct 26, 2008 11:14 am

Re: Tesla to start making Batteries for Home Solar

Post by musbane » Wed Apr 01, 2015 10:11 am

A few points.

Lithium batteries have several advantages. But one of them is their light weight compared to lead acid technology. This makes them ideal for vehicles. Houses on the other hand, don't much care about weight. So there will have to be a bigger spread in other attributes (cost, life, safety?) before they will be practical for home use.

RVs - especially for people who want to live off the grid would be an obvious though small ,relative to houses, market.

A house designed for solar will use only a fraction of the electricity of a conventional house. There will be lots of stuff like LED lights, propane referigeration, swamp cooler air conditioning, insulation, passive solar positioning,etc

User avatar
magellan
Posts: 3469
Joined: Fri Mar 09, 2007 4:12 pm

Re: Tesla to start making Batteries for Home Solar

Post by magellan » Wed Apr 01, 2015 10:17 am

Epsilon Delta wrote:I agree with the engineering, but I believe in economies of scale. It will make economic sense for the utility, or a commercial service, at substations before it makes sense at individual homes.
I'm not in this business or an expert in any sense, but I wonder if battery storage systems could actually have dis-economies of scale. I think this is the case in computing. It tends to be harder and more costly to build a single huge superfast computer compared to getting the same amount of MIPS across a distributed system.

So far, industrial photovoltaic systems haven't been able to generate the economies of scale many had hoped compared to roof top solar. I think battery storage systems could work the same way.

To me, part of the benefit is the distributed nature of the system. Many homes have free space already available and heat dissipation is probably less of an issue in a smaller system compared to a gigantic one. Plus the power will be available closer to the point of use compared to a centralized system that uses transmission capacity during peak hours to deliver the power.

User avatar
magellan
Posts: 3469
Joined: Fri Mar 09, 2007 4:12 pm

Re: Tesla to start making Batteries for Home Solar

Post by magellan » Wed Apr 01, 2015 10:20 am

lightheir wrote:Selling back to the grid is the best solution for now, but given solar's continued and progressive rise, we will soon reach the tipping point where utilities will no longer permit sellback of surplus energy to the grid, or at least hugely reduce the fees paid to sell back such energy.
This is a good point, but IMO the push back on net-metering is as much about politics and regulatory capture as it is about economics. My guess is that if utilities could eliminate net metering rules today, most would in a heartbeat. Why wouldn't they, since each kWh they're forced to accept reduces their profit?

IMO the big question is whether incumbent utilities, power producers, and transmission line operators are successful in manipulating regulators to curtail net metering to a point below its economic benefit.

There probably will be changes to net metering models over time, but the economics of users getting paid to push power back onto the grid locally are rock solid. Some form of net metering will survive unless consumers and watchdogs fall asleep at the switch and special interests are able game the system at the expense of economic efficiency.
Last edited by magellan on Wed Apr 01, 2015 10:40 am, edited 1 time in total.

Valuethinker
Posts: 34680
Joined: Fri May 11, 2007 11:07 am

Re: Tesla to start making Batteries for Home Solar

Post by Valuethinker » Wed Apr 01, 2015 10:33 am

Epsilon Delta wrote:
Valuethinker wrote:
magellan wrote: Distributing the batteries throughout the grid, close to where power will be used, helps with efficiency because in many areas, transmission lines to move electricity from power plants to users is as much of a capacity bottleneck as the powerplants themselves.
It's a good analysis. Remains to be seen if Musk has really 'cracked it' given the scale we are talking.

However my guess is at least 1% of US households might have other reasons to do this as well: frequent power outages etc. At which point, a lease payment from the utility for the additional storage capacity could turn into something quite valuable (effectively allowing the powerpack to be highly subsidized, or even free).
I agree with the engineering, but I believe in economies of scale. It will make economic sense for the utility, or a commercial service, at substations before it makes sense at individual homes. And for people who go on about the magic of the market, the utility knows the price in real time at least as well as you do. Residential time of use rates are currently vague approximations that will result in inefficient operations.
It might be that the savings an individual makes on land and buildings (ie not having to buy them), installation and cooling offset that. There are diseconomies of scale as well. I am not sure where this one will lie.

Yes re utilities have greater knowledge, which might underpin the economics of the business model: arbitraging between what it pays the homeowner and the true value of the electricity sold.
As for using batteries both for a backup and for grid balancing. Not a good idea. The utility will suck them dry just before the grid goes down. If you want reliability you need the backup to be sitting around not doing anything.
Good point. But there could be some kind of halfway point, a limit below which the utility does not discharge you (in my limited understanding of lithium batteries and the Prius, the charge has to be managed in any case for battery life).

User avatar
magellan
Posts: 3469
Joined: Fri Mar 09, 2007 4:12 pm

Re: Tesla to start making Batteries for Home Solar

Post by magellan » Wed Apr 01, 2015 10:35 am

Valuethinker wrote:A related problem is that the distribution grid was not built to take lots of power coming from distributed nodes. This is becoming an issue which will necessitate heavy investment.
There's certainly engineering to work out and we're talking about changes happening over decades, not years. However, IMO the key with battery storage systems, compared to wind or solar, is that the power pushed back into the local distribution system can be scheduled perfectly, based on the local system's instantaneous needs.

Today, valuable power is constantly lost in the distribution system for voltage stabilization. The voltage to your home doesn't stay steady on its own. Stabilization is done by a complicated and expensive system that generally involves having more power than needed available at all times, so a measured amount can be discarded to keep the voltage steady.

If battery system deployment were to become widespread, it seems a certainty that we'd eventually want them integrated into an intelligent grid, perhaps with voltage stabilization as a part of their job.

Valuethinker
Posts: 34680
Joined: Fri May 11, 2007 11:07 am

Re: Tesla to start making Batteries for Home Solar

Post by Valuethinker » Wed Apr 01, 2015 10:43 am

magellan wrote:
Epsilon Delta wrote:I agree with the engineering, but I believe in economies of scale. It will make economic sense for the utility, or a commercial service, at substations before it makes sense at individual homes.
I'm not in this business or an expert in any sense, but I wonder if battery storage systems could actually have dis-economies of scale. I think this is the case in computing. It tends to be harder and more costly to build a single huge superfast computer compared to getting the same amount of MIPS across a distributed system.

Perhaps the cost of land and any environmental restrictions (raising that cost). Advantages would be closer to the HV transmission network. Also as you point out, the cost of cooling could be a significant issue.
So far, industrial photovoltaic systems haven't been able to generate the economies of scale many had hoped compared to roof top solar. I think battery storage systems could work the same way.
I must admit my imrpession had been the opposite-- solar farms are c. 50% of the price? Hence some very big ones being built in California. However the Feed In Tariffs mandate a maximum size, so the economics favour rooftop installations (which are much more expensive).

WalMart, which is a company which never does anything without a hard nosed business case, finds installing on its rooftops to be economic. That is in some ways akin to 'utility scale' or at least it's 10x the size of a residential installation.

To me, part of the benefit is the distributed nature of the system. Many homes have free space already available and heat dissipation is probably less of an issue in a smaller system compared to a gigantic one. Plus the power will be available closer to the point of use compared to a centralized system that uses transmission capacity during peak hours to deliver the power.
Distributed generation has been promised for so long, and not come through. One of the reasons is US utilities have (in most cases) the capability to block Combined Heat and Power (ordinary reciprocating engines powered by natural gas (c. 30% efficiency) plus reuse of heat by any large complex of offices, hospital, industrial factory, student residences etc.-- giving you c. 80% overall thermal efficiency-- works well if there is a constant or steady heat load, although you can store hot water*). If you need to hop a power line across a public road to connect 2 big office blocks at a university, or 2 factories, you often can't do it.

My sense is DG will really take off if natural gas powered fuel cells become a reality. Then you have homeowners coming home, putting on the heat and needing juice to run the TV, the oven etc-- and the juice is right there as a byproduct of the heat.

Electricity storage doesn't really get you there (in terms of the kwhr or BTUs needed for heating/ AC) at least not yet. And the sunset (or bad weather) does it for home solar.

* the cylindrical storage tanks are impressive on these things - 10 meter columns say 2m in diameter.

But Musk is no idiot. I think he can see a synergy between cheap batteries and his solar business.

Valuethinker
Posts: 34680
Joined: Fri May 11, 2007 11:07 am

Re: Tesla to start making Batteries for Home Solar

Post by Valuethinker » Wed Apr 01, 2015 10:44 am

magellan wrote:
Valuethinker wrote:A related problem is that the distribution grid was not built to take lots of power coming from distributed nodes. This is becoming an issue which will necessitate heavy investment.
There's certainly engineering to work out and we're talking about changes happening over decades, not years. However, IMO the key with battery storage systems, compared to wind or solar, is that the power pushed back into the local distribution system can be scheduled perfectly, based on the local system's instantaneous needs.

Today, valuable power is constantly lost in the distribution system for voltage stabilization. The voltage to your home doesn't stay steady on its own. Stabilization is done by a complicated and expensive system that generally involves having more power than needed available at all times, so a measured amount can be discarded to keep the voltage steady.

If battery system deployment were to become widespread, it seems a certainty that we'd eventually want them integrated into an intelligent grid, perhaps with voltage stabilization as a part of their job.
Thanks. Interesting insights, all.

User avatar
tadamsmar
Posts: 7623
Joined: Mon May 07, 2007 12:33 pm

Re: Tesla to start making Batteries for Home Solar

Post by tadamsmar » Wed Apr 01, 2015 11:32 am

Tesla is already doing this with Solarcity and here is some info on cost:
...a 10-kWh Tesla battery (to power the refrigerator, lights, etc. in a power outage) under a 10-year lease for a $1500 upfront cost + $15/month. That amounts to $3300 over 10 years.
http://cleantechnica.com/2014/11/03/sol ... stem-cost/

This may be from a pilot program with no open spots till later this year,

User avatar
Epsilon Delta
Posts: 7318
Joined: Thu Apr 28, 2011 7:00 pm

Re: Tesla to start making Batteries for Home Solar

Post by Epsilon Delta » Wed Apr 01, 2015 11:35 am

magellan wrote: This is a good point, but IMO the push back on net-metering is as much about politics and regulatory capture as it is about economics. My guess is that if utilities could eliminate net metering rules today, most would in a heartbeat. Why wouldn't they, since each kWh they're forced to accept reduces their profit?

IMO the big question is whether incumbent utilities, power producers, and transmission line operators are successful in manipulating regulators to curtail net metering to a point below its economic benefit.

There probably will be changes to net metering models over time, but the economics of users getting paid to push power back onto the grid locally are rock solid. Some form of net metering will survive unless consumers and watchdogs fall asleep at the switch and special interests are able game the system at the expense of economic efficiency.
I agree but in this case solar owners also act as special interests. It's a problem when net metering sends the wrong price signals. For example in CA peak demand is in late afternoon. Solar on west facing roofs is, objectively, more valuable to the grid than on south facing roofs. But in the current pricing a kWhr is a kWhr so most of the solar faces south. Correcting the pricing by paying more in the late afternoon and less at noon will make the utility happier, but it will be fought by the south facing homeowners. Also if utilities are providing services to solar owners (so the solar owner doesn't have to buy a $500k battery) the utility deserves to get paid for that. How that happens has to be figured out.

bhsince87
Posts: 1578
Joined: Thu Oct 03, 2013 1:08 pm

Re: Tesla to start making Batteries for Home Solar

Post by bhsince87 » Wed Apr 01, 2015 11:40 am

HomerJ wrote:
bhsince87 wrote:Because around here, power from the grid goes out a lot. And usually, it's only for 2-4 hours at a time. Occasionally for a day or so. Many people have generators, but they're overkill for what we usually need.
Where do you live?
80 miles west of the mother ship. (Vanguard HQ, that is)
BH87

kolea
Posts: 1234
Joined: Fri Jul 11, 2014 5:30 pm
Location: Maui and Columbia River Gorge

Re: Tesla to start making Batteries for Home Solar

Post by kolea » Wed Apr 01, 2015 11:47 am

Some of the issues being voiced here are regulatory, not technical. If the utility companies are smart, they will figure out a way to work with PV, rather than trying to fight it. They are in the ideal situation to offer centralized storage. The problem they have is they have no way to store massive amounts of energy in excess of what the demand on the grid is.

It is true that de-centralizing the storage out to the homes has some advantages, but realistically there is a cheap option that exists today - good old lead acid batteries. Not elegant, but they work. And a lot cheaper than Lithium Ion. Who knows where this is going, but I see just as much opportunity in solving the problem centrally as I do at the end points.

In any event, this is all speculation. Elon Musk is involved in a lot more than EV; he also has Space-X and Hyperloop - his transport tube. Who knows what he is cooking up. I think he just likes to be the center of attention.
Kolea (pron. ko-lay-uh). Golden plover.

User avatar
magellan
Posts: 3469
Joined: Fri Mar 09, 2007 4:12 pm

Re: Tesla to start making Batteries for Home Solar

Post by magellan » Wed Apr 01, 2015 12:08 pm

Epsilon Delta wrote:I agree but in this case solar owners also act as special interests. It's a problem when net metering sends the wrong price signals. For example in CA peak demand is in late afternoon. Solar on west facing roofs is, objectively, more valuable to the grid than on south facing roofs. But in the current pricing a kWhr is a kWhr so most of the solar faces south. Correcting the pricing by paying more in the late afternoon and less at noon will make the utility happier, but it will be fought by the south facing homeowners.
Thanks for the clarification. I didn't realize that CA's net metering system doesn't take the time of production into account.

I agree that consumers are often the special interest fighting against time-based metering. Nobody likes to give up a subsidy, and in this case, plenty of consumers are enjoying a subsidy. OTOH, time-of-use metering is the best way to charge consumers the actual cost of what they consume. As I said before, it can cost 5-10 times more to produce and deliver power at peak times compared to in the middle of the night. From an economic efficiency standpoint, time-based metering is the right model, regardless of which way the meter is spinning.

The challenge is in getting everyone to fully appreciate that consuming power in the middle of a hot afternoon is much more costly than doing so at 2am. ...and to be willing to give up the free ride once they do.

SimonJester
Posts: 1474
Joined: Tue Aug 16, 2011 12:39 pm

Re: Tesla to start making Batteries for Home Solar

Post by SimonJester » Wed Apr 01, 2015 1:01 pm

One issue I think the industry needs to work on for whole house solar / off grid is to move products from AC to DC. How many of your electronic products today simply convert AC back to DC with a transformer, I'd say more and more. Now with LED lighting one could go DC for lights. AC motors are probably the last thing to go, think washing machine, hair dryer and so forth.
"They who can give up essential liberty to obtain a little temporary safety, deserve neither liberty nor safety." - Benjamin Franklin

bhsince87
Posts: 1578
Joined: Thu Oct 03, 2013 1:08 pm

Re: Tesla to start making Batteries for Home Solar

Post by bhsince87 » Wed Apr 01, 2015 1:42 pm

SimonJester wrote:One issue I think the industry needs to work on for whole house solar / off grid is to move products from AC to DC. How many of your electronic products today simply convert AC back to DC with a transformer, I'd say more and more. Now with LED lighting one could go DC for lights. AC motors are probably the last thing to go, think washing machine, hair dryer and so forth.
Funny you mention that. You can still find remnants of DC wiring in some of the older houses around here. Thomas Edison would be probably say "I told you so!"
BH87

kolea
Posts: 1234
Joined: Fri Jul 11, 2014 5:30 pm
Location: Maui and Columbia River Gorge

Re: Tesla to start making Batteries for Home Solar

Post by kolea » Wed Apr 01, 2015 3:12 pm

SimonJester wrote:One issue I think the industry needs to work on for whole house solar / off grid is to move products from AC to DC. How many of your electronic products today simply convert AC back to DC with a transformer, I'd say more and more. Now with LED lighting one could go DC for lights. AC motors are probably the last thing to go, think washing machine, hair dryer and so forth.
Converting AC/DC or vice-versa is very inefficient, as is converting DC voltages. It is also inefficient to transmit low voltage DC over long distances - the line loss is very high. Hence, AC is the norm for any power grid and that is not likely to change. If all power were local to your house, and all devices in your house used the same DC voltage, it would be best to run your entire house on DC. But as long as you are connected to a grid, and have varying voltages needed, there will always be AC as the standard. It is just far more efficient.
Kolea (pron. ko-lay-uh). Golden plover.

User avatar
Epsilon Delta
Posts: 7318
Joined: Thu Apr 28, 2011 7:00 pm

Re: Tesla to start making Batteries for Home Solar

Post by Epsilon Delta » Wed Apr 01, 2015 3:38 pm

SimonJester wrote:One issue I think the industry needs to work on for whole house solar / off grid is to move products from AC to DC. How many of your electronic products today simply convert AC back to DC with a transformer, I'd say more and more. Now with LED lighting one could go DC for lights. AC motors are probably the last thing to go, think washing machine, hair dryer and so forth.
It won't make much difference. The first thing most devices that run off DC do is run it through a DC-DC power supply to convert (and stabilize) the voltage. There's not much difference in performance or cost between a DC-DC and a AC-DC switching supply.

Some things run better from AC, others from DC but the differences are fairly small for the most part. The only thing that really needs AC are clocks, many of which are just cycle counters slaved to the 50Hz or 60Hz mains.

Ironically incandescent light bulb run quite happily on 120V DC, while at least some LED bulbs will not. Light bulbs are probably the highest volume and most cost conscious of all mains powered devices so saving a fraction of a penny to not support DC operation looks attractive.

User avatar
4nursebee
Posts: 966
Joined: Sun Apr 01, 2012 7:56 am
Location: US

Re: Tesla to start making Batteries for Home Solar

Post by 4nursebee » Wed Apr 01, 2015 5:27 pm

I am not normally a betting man but the announcement will not be home solar batteries. I am willing to bet large on this. I am willing to bet I do know what the product is, nobody else believes me.
THink about it, they don't even have a model 3 out yet, can't make enough batteries as it is...

I have a theory as to what the real product is going to be, have written about it a little on my blog...
but can't post links here.
PM if you want, or see my profile...

It's not a car
4nursebee

cutterinnj
Posts: 244
Joined: Wed Jun 01, 2011 10:08 pm

Re: Tesla to start making Batteries for Home Solar

Post by cutterinnj » Wed Apr 01, 2015 5:54 pm

4nursebee wrote:I am not normally a betting man but the announcement will not be home solar batteries. I am willing to bet large on this. I am willing to bet I do know what the product is, nobody else believes me.
THink about it, they don't even have a model 3 out yet, can't make enough batteries as it is...

I have a theory as to what the real product is going to be, have written about it a little on my blog...
but can't post links here.
PM if you want, or see my profile...

It's not a car
I don't doubt that we'll eventually get a truck, however, Elon Musk's tweet, "With all that solar power being generated, it almost feels like something is needed to complete the picture ..." all but guarantees that the big announcement will be batteries to store power for non-vehicular activities.
I think the "giga-factories" he's making is to gear up for this.

canderson
Posts: 218
Joined: Wed Dec 26, 2012 9:12 pm

Re: Tesla to start making Batteries for Home Solar

Post by canderson » Wed Apr 01, 2015 6:28 pm

Could these by an alternative to whole-home generators?

We live in a city, have natural gas and no fireplace. I'm always scared of long power outages in winter since we have no alternative heat source and running a generator isn't practical due to space/potential theft.

Could a battery like this placed high be tacked into your system and run when the grid is down? If so, sold. Probably cheaper than whole-home generators in some cases as well.

Post Reply