
Why batteries both thrill and terrify the U.S. utility industry - dotluis
http://www.bloomberg.com/news/print/2014-12-05/musk-battery-works-fill-utilities-with-fear-and-promise.html
======
msandford
From the article:

...said Ellen Hayes, a PG&E spokeswoman. “Having a solar panel that isn’t
connected to the grid is like having a computer that’s not connected to the
Internet.”

Patently false. It's a great way for them to rationalize their continued
existence. But as rooftop solar takes off and the "smart grid" fails to
materialize I suspect that you're going to start to see federated neighborhood
grids running at 48VDC.

Anything less than 50V isn't regulated by the NEC which is why you're supposed
to hire an electrician for new or major upgrades to your house wiring but
nobody cares if you put in low voltage pathway lighting, doorbells,
networking, etc.

That means that although you'll have to buy thick copper wires, people can
wire themselves up with their neighbors LEGALLY to share power. That's a big
deal. It doesn't take all that many people to be connected to substantially
smooth out fluctuations. Most A/C doesn't run all the time, it's only supposed
to be about 15 minutes out of every hour. So if I and four neighbors team up
then we might need 5kW of solar panels between us instead of 5kW each. At
least if it's somewhere sort-of temperate where A/C isn't crucial at night.

The power electronics to make this happen are getting cheaper by the day. Sure
it means having to talk to your neighbors and some retrofitting, but that's
doable. And with a lot of new equipment having VFDs in them from the factory
(refrigerators, mini splits, even a lot of A/C compressors) it means that the
cost of converting them drops even more.

~~~
gambiting
5kW at 48V is over 100 amperes - absolutely no offence to you personally, but
anyone handling this without training and precautions is absolutely stupid, no
matter how thick the cables are.

~~~
ddeck
While you are correct that 48V is definitely sufficient to cause injury/death
in certain circumstances, it's not the current that matters here (e.g. a
1V/5000A supply would have a lower risk of shock).

What will hurt/kill you is the amount of current passing through your body (in
particular your heart) and that is determined by the resistance of your body
and the potential difference of where it's flowing from/to (I = V/R).

Interestingly, the current required for ill effects is significantly higher
for DC vs AC (at lowish frequency) [1]:

    
    
      BODILY EFFECT     DIRECT CURRENT (DC)    60 Hz AC     10 kHz AC
      --------------------------------------------------------------- 
      Slight sensation     Men = 1.0 mA         0.4 mA        7 mA 
      felt at hand(s)    Women = 0.6 mA         0.3 mA        5 mA 
      --------------------------------------------------------------- 
      Threshold of         Men = 5.2 mA         1.1 mA       12 mA 
      perception         Women = 3.5 mA         0.7 mA        8 mA 
      --------------------------------------------------------------- 
      Painful, but          Men = 62 mA           9 mA       55 mA 
      voluntary muscle    Women = 41 mA           6 mA       37 mA 
      control maintained                                           
      --------------------------------------------------------------- 
      Painful, unable       Men = 76 mA          16 mA       75 mA 
      to let go of wires  Women = 51 mA        10.5 mA       50 mA 
      --------------------------------------------------------------- 
      Severe pain,          Men = 90 mA          23 mA       94 mA 
      difficulty          Women = 60 mA          15 mA       63 mA 
      breathing                                                    
      --------------------------------------------------------------- 
      Possible heart        Men = 500 mA        100 mA             
      fibrillation        Women = 500 mA        100 mA             
      after 3 seconds                                              
      ---------------------------------------------------------------
    

The linked article suggests an across the chest current of at little as 17 mA
could potentially induce fibrillation. At 48V, this is equivalent to a hand to
hand (assuming the second hand is the exit point) resistance of ~2,823 Ohms.

While is this a very low resistance for the body, it's possible with wet hands
and a large surface area in contact with the voltage source.

[1]
[http://www.allaboutcircuits.com/vol_1/chpt_3/4.html](http://www.allaboutcircuits.com/vol_1/chpt_3/4.html)

~~~
sliverstorm
Fibrillation is a problem, but so are electrical burns. 5kW is going to cause
a lot of tissue damage.

~~~
marcosdumay
Your body does not let the 5kW go through it.

~~~
sliverstorm
While I believe that precisely 5kW will not travel through your body,
considering you can arc weld with 48V/100A and your household 120V/10A (1.2kW)
sockets can cause severe burns, I think it's safe to say this hypothetical 5kW
source could do a _lot_ of damage.

Unfortunately I specialize in low voltage, not high voltage power electronics.

------
ChuckMcM
This is something I've been considering of late. I was an 'early adopter' for
Solar and have had 5kW of panels on my roof for 14 years now. Initially we
were on a 'watt for watt' type rate schedule with a flat true up at the end of
the year (basically net usage would be billed every 12 months). This was a
good deal for me, and a bad deal for PG&E apparently. Over the years they have
morphed that into something much more in their favor and with the help of
"smart" meters have factored in various timing aspects which all work toward
increasing how much I pay PG&E even though I am using about the same amount of
power that I was before.

The only answer then is to go 'all in' and just cut them out of the equation.
But battery maintenance is a huge challenge with lead-acid packs, a fire risk
with lithium ones. I'd love to have a locally owned and operated 'storage
depot' where I could shove my excess power to the depot, and pull power when I
needed it (like being grid tied) but consolidate and amortize the cost of
maintaining the power storage component across a bunch of customers.

~~~
Raphmedia
Can you legally do something like use the solar power for your lighting or
small appliances and use the company's electricity for your heating? With
different sockets and wires?

~~~
ChuckMcM
Yes, I could do that.

What I can no longer do is come out revenue neutral if I generate exactly the
same number of kwH that I consume in a 12 month period.

~~~
infogulch
I don't think that would be fair anyway. There is more value in electricity
than net kwH used in a year. Ignoring other value that power companies provide
(such as supplying for large demand fluctuations over days and seasons) and
asserting that you should get them for free seems disingenuous at best.

~~~
ChuckMcM
Interesting use of the term fair. If I had 'super capacitors' or pretty much
any 98% or better charge storage device I could take my house off the grid and
give the power company zero dollars for power. In my ideal world I would set
up solar to nominally charge the base load charge supply for my house, and
power the house from the base load charge supply. In the event my base load
charge supply dropped below a set limit, I'd use natural gas to run a fuel
cell for some number of hours to get the base load charge supply back into the
right zone. I continue to use gas for heat applications (stove top, dryer,
house heater, water heating) but would be no longer part of the electricity
grid.

Right now, to do this costs more than the 'surcharge' I'm paying PG&E to be a
utility with electricity on demand. But once the economics switch I'm going to
kick their electricity service to the curb. And I consider that both right and
fair.

------
jarrettc
The article suggests that solar panels could be an "existential threat" to
power companies. For those of you who are familiar with the math of solar
panels, how realistic is that prediction? How much of a normal home's energy
needs could be supplied by solar panels, assuming the panels covered the
entire surface area of the roof? How much is the ROI on solar panels likely to
improve in the foreseeable future? (I've heard estimates of 5-8% annual return
for 2014.)

~~~
djrogers
I installed a 10kw system ~15 months ago on my 3600sq ft house. Average
electricity costs was ~$6k/year before the panels, the first year on solar to
total cost for the year was $300.

That $300 worth of electricity for the year is before I've been able to talk
the wife in to replacing our incandescent bulbs, swapped out our old pool
pump, etc etc - I could easily get that down to below 0 with a small
investment in bulbs. So in my case at least, it was trivially easy to get to a
net-zero usage.

A few $$ notes - the system cost $37k, I got 11.1k of that in a tax credit
from the feds, so my net cost was 26k. I'm saving 5.7k/yr, which means my
break even point for the system is 5 years. In 5 freaking years I'm making
money from my solar panels! And I don't have to write a $500 check to PG&E
every month. It's a beautiful thing...

BTW - the above numbers (plus my severe aversion to debt) are why I'm so
against solar leases. If we had a solar lease, we'd still be stuck with
monthly payments, would have trouble selling our house, and would be stuck for
20 years.

~~~
mrfusion
$6K/year sounds really high no? My neighbor pays $100-150/month for a 3200
sqft house.

~~~
Shivetya
Welcome to a fully regulated rate structure, throw in the combined weight of
years and years of "its for the environment" and the costs go to the people
who have the least voice and for many the least ability to pay.

The have so regulated pricing and punitive structures into service there that
they have to have assistance programs just to alleviate the burden on middle
income and lower consumers.

------
diafygi
For people who want to learn more about the complexities in this topic, I
highly suggest listening to the Energy Gang podcast[1]. A ‎senior editor at
Greentech Media, principal lobbyist at a huge energy lobby firm, and the
founder of Sun Edison get together once a week to talk about at latest news. I
work in the new energy industry, and everyone I know in this industry listens
to this podcast.

For example, a few months ago, they talked extensively about how Hawaii's
utility is basically falling apart since it can't find a way to compete with
solar now that solar is at grid parity, and solar+storage is on the verge of
reaching off-grid parity[2]. What happens when half of your customers simply
leave? We're about to find out over the next few years.

Also, if you want to learn more about tech entrepreneurship in the solar, I
recommend reaching out to the SfunCube[3].

[1]:
[https://www.greentechmedia.com/podcast](https://www.greentechmedia.com/podcast)

[2]: [https://soundcloud.com/the-energy-gang/can-the-us-
government...](https://soundcloud.com/the-energy-gang/can-the-us-
government#t=19:55)

[3]: [http://www.sfuncube.com/](http://www.sfuncube.com/)

------
oblio
One thing to note - while this all sounds very exciting and optimistic, a huge
percentage of energy is actually generated by coal fueled plants:
[http://www.worldcoal.org/resources/coal-
statistics/](http://www.worldcoal.org/resources/coal-statistics/) \- 40%.

Let that sink in for a while. More than 1 century after the introduction of
gas and oil fueled power plants and more than half a century after the
introduction of nuclear power plants, coal is still powering almost half of
the world. Perhaps even this PC on which I'm writing this comment.

Don't expect a revolution. Expect an evolution that will take another half a
century or more :)

~~~
okaybutthen
Only because right now the economics of coal fueled electric plants are
favorable.

Coal based plants will die down as cost per kWh of ocean tide, wind, solar,
etc are optimized.

------
nostromo
Another reason: consumers subsidize industry.

Look up your local utility rates for high demand users. (These usually include
things like factories or data centers.)

They pay a lot less for energy than you do at home -- even though the power
plant doesn't care if the electricity is used for your hair dryer or smelting
aluminum.

If the consumer goes solar, industry will suddenly have to pay their fair
share of the bill.

~~~
maratd
I experienced the exact opposite with PSE&G in NJ. I had both a residence and
an office in the same municipality. I was paying a higher rate per kWh at the
office. Almost twice as much. When I asked them about it, they said it was
because I was at an address marked as a business.

I think this depends heavily on state-level regulation of the utility and
market conditions for your segment.

~~~
mikeyouse
To be fair, you're talking about a third distinction in the eyes of utilities.
They typical tier pricing by residential, commercial and industrial. It's not
uncommon for commercial power to be more expensive than residential, but it's
extremely uncommon for industrial power to cost more.

------
rdl
Even if this didn't make sense in California (it might), it makes huge sense
in Hawaii -- power is $0.30-0.50/KWh, and they're starting to look at higher
charges for grid-connected solar users (connection fees), and lower purchase
prices for power.

If I could handle peak and steady state loads off-grid there, I'd be very
tempted. I was assuming water pumping storage, or scheduling loads, and a
diesel or propane generator for extreme peaks (running tools), but this might
work too.

~~~
amalag
This was from last year, I don't know if things are still this way there.

[http://www.scientificamerican.com/article/a-solar-boom-so-
su...](http://www.scientificamerican.com/article/a-solar-boom-so-successfull-
its-been-halted/)

------
jhallenworld
I learned recently that nearly ideal batteries already exist for the purpose
of storing energy from solar: nickel-iron batteries (side note: Edison made
more money from selling these batteries than from any other invention). They
last a very long time (50 years), are durable (not damaged by full discharge)
and can be made from cheap materials. The energy density is not high, but this
is probably not a major issue for home energy storage.

~~~
infogulch
I didn't know about NiFe batteries. With a long lifetime, deep discharge
durability, and cheap non-toxic construction they look quite promising. Except
overall efficiency isn't great, and it looks like they require regular
maintenance. Of course, maintenance becomes less of a problem at
neighborhood/grid-local scale.

------
kefka
Why are they so scary? They're just a whole bunch of 18650's, with integrated
cooling chambers and nice chargers.

I just picked up a pack of 10 from ali express for $14. The charger was $10
and can charge 2 batteries in about 1/2 hour. The American markets don't see
them unless you crack open dead laptop batteries and test.

~~~
mullingitover
I've seen plenty of 18650s outside of laptops. They're extremely popular in
the electronic cigarette scene.

~~~
defective
Yep, and we inherited them from the flashlight enthusiasts.

------
bdamm
Even if individual homes can sustain themselves on solar power, there are many
homes and even more businesses that cannot. Even if people are storing power
in batteries and charging them up for later use when power is cheap
(determined locally) you still need the utility to be that conduit to get the
power from the (distributed) sources to the (distributed) consumption.

Can the existing grid handle this kind of workload? Yes, if it is managed well
and controls are in place to prevent delivering more power into the network
than it can handle.

------
grecy
This is materializing in Australia right now.

My parents just put 5kW of solar on their roof, and are still tied to the
grid, selling some back for a tiny fraction of what they buy it for at night.

The government has now mandated that everyone on the grid must pay an "access"
fee every month, even if they use nothing, and they are limiting how many
people in any neighborhood can go solar and sell power back to the grid.

It's no secret the government are doing this to protect their friends in the
coal and electricity industry.

~~~
TrainedMonkey
So what would happen, if government did not mandate that? Some people would go
completely off grid, this would raise prices for everyone else. In some
communities it would not be economical for electric company to operate at
all[0]. Moreover they can't just leave this over to the cities because rich
communities would go off grid and raise prices for others in the area. While I
am sure there is "friendship" angle you are coming from is real issue is far
more complex than that and there is no simple solution.

[0] And given utility status of electrical companies they are mandated by the
government to do so anyways.

~~~
JoeAltmaier
Another issue is sunlight. Most folks own land but not the right for sunlight
to fall on it. Someone next door can shade your roof with their large solar
collector; now you HAVE to connect to the grid. Such disputes will interfere
with the smooth deployment of roof-mounted solar energy panels.

------
elihu
What is the price of a residential battery? Let's say you need 10 kilowatt
hours to last from sunset to dawn (you might need more some nights, but if
you're still on the grid, 10 kwh might be enough most of the time, which is
what matters).

The Tesla model S has a 60 or 85 kwh battery. I don't know what the cost of
the battery alone is, but it's probably pretty expensive. For fixed
residential, you wouldn't need to use the most energy dense cells available,
so it might be cheaper.

Wikipedia has a price per kwh comparison, showing lead acid considerably
cheaper, though that might not be up-to-date with the price Solar City and
Tesla pay for Lithium Ion cells.

If lead-acid is $250 per kilowatt hour, that puts a 10 kwh battery at $2500.
Not too bad, but if they only last six years or so, that's a pretty big part
of the ongoing cost of maintaining the system. How does lithium ion compare on
price and longevity?

[http://en.wikipedia.org/wiki/Electric_vehicle_battery](http://en.wikipedia.org/wiki/Electric_vehicle_battery)

~~~
jared314
> The Tesla model S has a 60 or 85 kwh battery. I don't know what the cost of
> the battery alone is, but it's probably pretty expensive.

As of 2013, the 60 and 80 kwh batteries are approximately $10k and $12k
respectively. [1]

[1] [http://www.teslamotors.com/blog/2013-model-s-price-
increase](http://www.teslamotors.com/blog/2013-model-s-price-increase)

------
nullgeo
Oh how funny, 130 years ago Tesla scared the hell out of some battery company.

------
yason
Since they also make stationary batteries I wonder what would it cost to
manufacture small flywheel energy storage units for homes instead.

To an extent, those are used in bigger grids to balance out peak production
and peak consumption: they rotate in a vacuum on magnetic bearings and require
very little if any maintenance.

Those big boys probably cost a lot but a consumer-grade flywheel which could
spin for, say, 24 hours and be slightly less efficient (wrt. input-to-output
and friction losses) could still be a big deal to even out daily usage.

------
dmritard96
The interesting situation is that companies regulated as a utility, presumably
because a competitive environment for infrastructure isn't always practical
(defacto monopolies) is facing competition hence creating some interesting
questions.

------
cportela
Thank you for posting this as the print link. Literally a simple task, but
again thanks.

------
DanKlinton
This Elon Musk guy sounds more and more like Tony Stark from Iron Man :)

~~~
falcor84
Musk was indeed was an inspiration for the movies (and did a cameo on Iron Man
2)
[http://content.time.com/time/specials/packages/article/0,288...](http://content.time.com/time/specials/packages/article/0,28804,1984685_1984745_1985495,00.html)

~~~
gohrt
It seemed to me that Iron Man (comic) was an inspiration for Elon Musk's
persona.

------
jcromartie
Entropy will increase...

Everything will become increasingly decentralized and democratized thanks to
the miniaturization and increasing efficiency of technology. It's all but
inevitable. The only thing that can stop it is politics.

------
JoeAltmaier
Rooftop solar would have a very hard time supplying the same current feed your
power company has. A few back-to-nature Californians may be satisfied with the
battery-solar combo straw man in this article; most of us want our TV and
microwave too.

~~~
mabbo
The threat isn't that people don't need _any_ power from the electric company,
it's that people need very little of it. Demand dropping to 5% of your usual
business model might as well be demand dropping to 0%.

~~~
JoeAltmaier
Some of that drop can be beneficial to the power company. They are always on
the edge of capacity, because building more capacity is very (billions)
expensive, and at first you don't need all of it, so the marginal cost of
expansion is huge. Deploying solar across the area could postpone the need for
generator expansion, and save money for current customers.

~~~
hga
Depends on the type of capacity. I gather that peaking power is typically
provided by gas combustion turbines
([https://en.wikipedia.org/wiki/Gas_turbine#Industrial_gas_tur...](https://en.wikipedia.org/wiki/Gas_turbine#Industrial_gas_turbines_for_power_generation)),
which have much lower capital costs and much higher operating costs (including
maintenance). But if you need more baseline, then, yeah, you're going to be
spending a lot of money, although I'd expect modern gas powered baseline
plants to be relatively cheap (don't ask about nuclear, and fuel handling is
much easier than coal, plus coal is nasty dirty stuff that needs exhaust
cleaning, and disposal of ash).

~~~
abakker
I think Joe might have been referring to transmission and switching costs.
Adding generation capacity to the grid usually means that you need more
substations, and control infrastructure.

