Tesla Gigafactory may be gamechanger...for utilities...

One of the reasons cities get a low rate for street lights is it cheaper to keep the power plant running than try to throttle back. So street lighting electrical rates are low. But if this power can be stored and released later to be bought at a higher rate . . . the city street lights will be competing with the businesses and homes of their tax payers. The only mitigation is efficient, high-power LEDs might keep the lights on.

Bob Wilson

 

This is what I posted at Cleanmpg about this.

The article wasn't clear on how SolarCity is using the batteries, which explains how it got it wrong. It isn't to simply store solar generated electricity for off grid use, or for emergency back up, which is a plus for installing it. The batteries are for peak shaving, or time shifting, the facilities' electric use. It charges up at night when rates are low to displace electric use at peak demand when rates are high.

SolarCity is bundling it with their PV panels, but I doubt there is any excess PV electric for the batteries at a So. Cal. Wal-Mart running the A/C. Toyota has installed such battery banks alone at some of their Japan dealers.

Lead-acid is cheaper, but could be an issue for roof installations because of their weight, though I admit that is likely a small concern. SolarCity is probably using new Li-ion, but selling at cost or loss because what they really want to use is in short supply now, dead traction packs from plug ins.

Dead is relative. A pack judged dead for a car, hybrid or plug in, still has about 80% capacity left, which is fine for peak shaving and emergency power. For their units, Toyota used NiMH cells from old hybrids. Musk is planning ahead. With increasing plug ins on the road, there will start to be a steady supply of old packs over time. Using them after the car is done with them is a better use of resources than recycling them right away. that could also allow the now batteries to be sold at slightly lower if Tesla gets the old pack back, and sells it to SolarCity.

The article was wrong about utilities being scared, because it isn't about going off grid. The smart companies will welcome peak shaving. It lets them run base load plants at a higher, more efficient load during the night, and reduce the amount of peak output they need to build.

DemandLogic Demand Response - Commercial Solar Solutions | SolarCity

 

I'm not sure this will threaten the utilities business model but those that adjust to it will greatly benefit from it. This will help the cooperatives immensely and may spark an increase in the number of local cooperatives (as a small business) instead of the typical huge utilities who typically cut customer service. The batteries may get drained by the utilities/cooperatives after the sun goes down when everybody gets home and solar panels are no longer charging them (and the wind dies down). This will also allow the homeowner/business to provide instantaneous power on demand when needed instead of firing up a coal/oil/NG generator.

The only sticking point I see is the utilities may demand they get electricity at a wholesale price instead of retail. Which is odd because they are selling it to the homeowner at retail. But that is where a local cooperative may help, to keep the prices about the same whether being supplied or delivered.

 

SolarCity is using the batteries for peak shaving, so they won't get drained at night unless the power goes out. Most of the charging will actually be at night.

It is just like Toyota using old Prius batteries at their dealers for peak shaving. SolarCity is just bundling in PV.

 

Utilities are not against any means of energy production per se, so long as they own it or monopolize the distribution. To the extent that PV is owned and consumed by the homeowners themselves, it is an existential threat to their business model.

 

Yes, but the way SolarCity is using batteries doesn't add to that threat since they are mostly charged at night from the grid.

 

If you mean the homeowner buys the batteries, and the utility fills them up at night with coal based energy that is then sold during the day at retails rates -- well, PM me for a GREEAAT deal on a bridge.

 

SolarCity isn't selling these peak saving/time shifting units to home owners. They are for businesses. A grocery store in southern California or Arizona charges the battery up in the middle of the night when rates are low, and then uses the battery and PVs to run the lights, refrigerators, and A/C during the day when rates are at their highest. The battery is just being used as buffer to shift grid bought electric from when it is needed to when it is cheaper without having to pay workers more to come in on a night shift.

Toyota is doing this right now on some of their Japan dealers using old hybrid batteries, just without the PV. If the PV over produces, the battery could use that power at night then, but that isn't how SC marketing them. The article author didn't seem to get that.

My guess is that SolarCity will eventually use old batteries from Teslas for this.

 

^^ I see.
I penciled out the costs of substituting battery storage at home rather than pay for a grid connection not too long ago. I was better off paying $30 a month to the utility, even though my home is a low-consumption device. Businesses would face worse numbers because they would have to enter into TOU agreements and pay high daily rates when the battery store was consumed.

Call me skeptical. And call me *very* skeptical that this is the great GigaFactory business plan.

Now you might be thinking that old Tesla batteries can be resold so cheaply for this emerging market that it becomes profitable for both Tesla and the storage consumer, but the Prius is a cautionary tale: one weak module takes down the battery. And as we have seen, battery refurbs are expensive and rarely a better idea than buying new.

 

Perhaps old batteries won't used, but the main idea isn't about going off grid as assumed. Jus for high electric users to save some on rates. It also has pluses for the utility; base plants get used at more efficient loads at night, and less strain during peak.

 

Sooner or later the AC module concept used on individual solar panels will become standard on each battery cell. Each cell will have it's own charge and discharge control to a single bus voltage. The Tesla battery already does some segmentation like this and the payoff is too good for it not to happen for every battery cell in the near future. The amount of silicon needed and the cost to do this is mighty low now. The issue is not cost of the individual circuitry, but the cost of industry changing to having a whole slew of car batteries instead of a single traction battery.