
Batteries for homes and businesses could already make economic sense - Mz
http://www.washingtonpost.com/news/energy-environment/wp/2015/10/07/how-installing-batteries-in-homes-and-businesses-could-already-make-economic-sense/
======
beambot
In order to "dispatch" power as-needed, you need buy in from municipal power
companies to grid-connect the supply (or generation). As we're seeing (eg. in
Hawaii), the power company becomes less-and-less incentivized to permit grid-
connections as the rate of decentralized supply (or generation) increases.

What I'd really like to know: How will the power companies adapt to new,
decentralized generation (or storage) on a massive scale? Or alternatively:
The municipal power companies budgeted their massive expenditures over
decades; does this analysis account for all the expenses municipal power
companies will necessarily incur (and pass to consumers) if the status quo
shifts?

~~~
toomuchtodo
Homeowners in Hawaii are using batteries to go completely off the grid, so as
to not be required to get permission from the utility for their solar grid tie
connection.

The upside is, once the utility comes around to investing in their
transmission infrastructure, they can receive power from those houses.

[http://www.nytimes.com/2015/04/19/business/energy-
environmen...](http://www.nytimes.com/2015/04/19/business/energy-
environment/solar-power-battle-puts-hawaii-at-forefront-of-worldwide-
changes.html)

“I’ve actually taken people right off the grid,” he said, including a couple
who got tired of waiting for Hawaiian Electric to approve their solar system
and expressed no interest in returning to utility service. “The lumbering big
utilities that are so used to taking three months to study this and then six
months to do that — what they don’t understand is that things are moving at
the speed of business. Like with digital photography — this is inevitable.”

------
bavcyc
Power is currently dispatched according to the most efficient units run most
frequently. Peaking units run only when it is most cost effective, i.e. power
is needed and there are not cheaper options. Yes it is possible to store the
energy (one method is pumped storage) for peak shaving, but different methods
have different break even points.

Also of interest is the Clean Power Plan and how it will change the generation
mixture.

A battery is not available 24 hours as the article indicates. There is the
time to charge and the time to discharge. There is also the time for
maintenance activities on the batteries.

If a battery system or solar system is installed then it breaks and power is
wanted from the local utility, the utility has the costs associated with
supplying that power with less time in use although it is expected to be
available at need and at the peak demand for all customers. Will end users be
willing to pay for the emergency back up or will another solution be found?
How long will it take to repair battery or solar when it breaks? And what do
you do for power until is repaired (if you don't use the utility)?

Using more energy efficient building technologies, e.g. ICF or something like
enteria.com; will probably be useful in combination with batteries. And using
a chest fridge as a refrigerator can also help:
[http://newlifeonahomestead.com/convert-chest-freezer-to-
frid...](http://newlifeonahomestead.com/convert-chest-freezer-to-fridge-
solar/) (one example from the google search results).

It is an interesting time as energy use and supply are modified. 30-50 years
ago, a 15-50 minute outage wasn't that big of deal, but today it is expected
that power is always available. Interesting how our perspective changes.

------
chaostheory
It already makes sense in the 3rd world where rolling blackouts and unplanned
blackouts are quite common.

~~~
dghughes
It makes sense in the first world too to have a stable source of power at all
times.

By that I mean medical reasons I know someone who has a home dyalysis machine
and absolute uninterruptable power is required.

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MBlume
I honestly can't understand what use patterns the article is suggesting.

"During these hours, the report argues, the battery could be “dispatched”
elsewhere to helps smooth supply and demand on the grid"

Do they actually mean moving the battery, or something else?

~~~
toomuchtodo
Arbitrage. The price of power changes every few minutes (wholesale) to a
utility. They shield you from this with flat rates per kwh or tiers. With
battery arbitrage, you switch to a time of day metering scheme where you're
exposed to dynamic pricing. The benefit, of course, is that you can charge
when power is cheap, and run off your battery when power is expensive.

A great example: I reside in Illinois for part of the year. My utility
provides power from nuclear plants, which cannot be idled. That means, at
night, I can get power between midnight and 5am for about 1 cent/kwh. If
batteries get cheap enough, cheap power + batteries means I save money.

Most electric vehicle charge controllers are already "smart" in this regard,
and can charge when power drops below a certain price.

~~~
dogma1138
The only problem with this is that this will be a zero sum game. If peak power
consumption drops electric companies will start charging higher rates for off-
peak hours or drop the off-peak rate completely.

Anything that will eventually lower the revenue of the electrical companies
won't really be supported by them, however if they can employ batteries to
"flatten" their peaks they might be contempt with keeping the current rates as
long as is financially beneficial for them.

~~~
ZeroGravitas
It's not zero sum.

The peak hours are when electricity is most expensive to generate. And
transmission lines etc. need to be sized to the peak.

That's one of the reasons that rooftop solar actually makes a lot of economic
sense anywhere that aircon is used. However, the people who generate that
electricity receive no direct reward and will probably be accused, by the very
utility that benefits, of being subsidy junkies or parasites.

When utilities have calculated the "value of solar" its come out as much
higher than the price currently paid to homeowners.

~~~
caseysoftware
Exactly.

Personally, I love the idea of neighborhood-level collection and distribution.
If everyone is collecting throughout the high-output times, when the high
demand times come, less has to come from the overall grid. Also, when power is
cut/damaged for an area, systems could be smart enough to prioritize across
the neighborhood.

Imagine a system that keeps the refrigerators and freezers running - to
protect food - but doesn't run the AC or dishwasher or lights. Not perfect but
_way_ better than losing food.

~~~
dogma1138
It's a zero sum game from the point of the consumer, if you "exploit" the
current day/night difference and the electric companies start to lose money
they'll increase the tariffs to compensate.

~~~
caseysoftware
If dollars are the only thing you're counting. But I said nothing about money
that in my comment.

------
DorothyS
There always is sense in self-renewing energy sources. Especially, when it
comes to saving our environment and lives. Implementing of such batteries
would be beneficial for everyone. And it would finally let the mankind get rid
of petroleum fever, which is now a source of all evils and the main cause of
all wars.

------
transfire
If we could get in-house/building DC power (not to replace but to complement
AC power) and get industries to make digital products work with this we could
get another substantial savings in energy efficiency. Plus digital products
would cost less b/c they wouldn't all need AC to DC adapters.

~~~
brandmeyer
Unfortunately, unplugging DC power plugs under load tends to damage them much
more than the equivalent AC plugs. Similarly, DC rated circuit breakers and
fuses are much larger than their AC counterparts. The reason is that the zero-
crossing of the AC voltage waveform naturally allows the developed arc an
opportunity to be extinguished. DC current/voltage has no such zero crossing.

~~~
badsock
I believe transfire is talking about low voltage DC.

~~~
simcop2387
The problem with low voltage DC wiring is that it requires much more metal to
prevent serious losses in the lines. You could switch to higher in the lines
and then a converter in the wall but then you're back to the same circuit
breaker problem. AC deals with this by the fact that zero crossing gives a
great way to break arcs and you can convert it to DC really efficiently.

~~~
caf
I believe the idea is probably to have one large switchmode converter running
off the mains at the POE that supplies, say, dual rail 20VDC / 5VDC throughout
the building, replacing the umpteen smaller converters in the average house.

Not sure it would end up being a net win.

~~~
simcop2387
That's the point, if you don't do the conversion to low voltage at the source
you lose a lot in losses from the resistance in the lines.

Let's say you're using the normal 14 gauge solid core wire commonly found in
houses right now for a 5V supply. A 200ft run of that in the house (both ways)
isn't out of the question if there's a central supply in a 2 story building.
That's about 1 ohm [1], which doesn't sound like much at first until we look
at what it ends up meaning.

A phone might take an 1 Amp to charge at it's fast rate (tablets 2 or more),
so we've got 1 Amp, with a 1 Ohm resistance. That means we're going to have a
1 Volt drop to that outlet, which means the phone is likely not going to
charge at the correct current since it'll only see 4 Volts at the outlet. It
also means you've just had a 20% loss in the power line in order to have a
larger central power supply.

Combine that with the fact that most Switch-Mode Power Supplies aren't
actually that efficient when not under load (part of the problem) then it
might not be unreasonable to have it running at 80% efficiency to begin with.
At this point you're down to 64% total efficiency instead of the 80-90% that
the small wall warts end up getting you.

You could use a higher voltage, 48V isn't uncommon because of the telephone
industry, but then you need conversion at the outlet again and end up with the
same problem you've got with wall warts.

The other option is to use more copper to carry the current, say 10 gauge,
which brings the losses to 0.4V and about 10% losses, but you need 150% more
copper than 14 gauge.

[1] [http://www.cirris.com/learning-
center/calculators/133-wire-r...](http://www.cirris.com/learning-
center/calculators/133-wire-resistance-calculator-table)

~~~
upofadown
Trying to regulate 5V across 14Ga wiring isn't anything anyone would do. If
48V became some sort of DC standard then devices would work off 48V. That
might not make sense of course and how much sense it might make could depend
on line voltage (120V vs 240V).

There is a cultural thing here too. If you live in a place where all heating
is done with combustion then there is no particular reason so not do
everything with low voltage DC. Now that lighting is LED based there wouldn't
be anything that would need the higher voltage and power.

~~~
simcop2387
No it's absolutely not what someone would do, but it is what the grandparent
proposed, that's why I addressed it. I'd love to see it used for more
efficient lighting, as if it was done correctly I think you could get some
pretty nicely efficient and long lasting lights that way with a bigger better
current driver for the leds. This might be a good idea to move Track lighting
to since they'll have more freedom on the sockets and interfaces.

As far as other devices needing the AC power, you've got hair dryers, kettles,
vacuum cleaners, air conditioners, water pumps, etc that all need more power
than would be reasonable with low voltage DC (some might need 25-50 amps to
run at the same power they currently use). All of that just means you'll still
have the AC running through the house for a very long time anyway, so you'll
end up with nothing changing.

------
Shivetya
in the home, no thank you.

however within substations, or perhaps subdivision localized power storage
facilities, or lets go even further, charging stations for cars, I can see it.

Utility setup and managed charging stations replete with a lot of battery
storage soaking up wind, sun, and base line power when off peak usage times,
providing both a source to recharge EVs and serve peak power usage times. To
insure adequate power on hand they could charge EVs based on time of day to
move people off peak.

because honestly, the last thing I want in six hundred to thousand pounds of
lithium batteries in my home.

~~~
snowwrestler
I've got pressurized natural gas lines into my basement and running to my hot
water heater, to my furnace, and to my stove. These appliances actually
release and burn that gas, sometimes only a foot or two away from me.

It's kind of crazy, if you think about it. I barely know a thing about how
these work and why they are safe. I just pay professionals to show up and
install or maintain the things--and that happens very rarely. No one has
looked at my stove or water heater since the home inspection years ago.

My point is, there are seemingly risky technologies all around us, which we
ignore out of familiarity. I'm not going to buy the very first Tesla battery--
I'm not an early adopter in general--but I see no reason to reject lithium-ion
battery technology entirely. I mean, I press a small lithium-ion battery
directly against my head on a regular basis, with only a thin sheet of glass
to protect me.

