[HN Gopher] California breaks 1 GW energy storage milestone
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California breaks 1 GW energy storage milestone
Author : philipkglass
Score : 48 points
Date : 2021-07-15 16:21 UTC (6 hours ago)
(HTM) web link (pv-magazine-usa.com)
(TXT) w3m dump (pv-magazine-usa.com)
| jedberg wrote:
| As a Californian who has been watching the CalISO web page since
| the 90s, what I find most interesting is that the peak usage and
| total generation now is pretty much the same as it was in the 90s
| (~50MW).
|
| Based on the energy mix, it looks like lost coal capacity has
| been replaced with solar and other green energy, and demand has
| gone down relative to population because of efficiency
| initiatives and rooftop solar for the largest home consumers
| (rich people).
|
| I'll bet demand falls even faster as home energy storage gets
| cheaper and more prevalent.
| vondur wrote:
| California still imports a large amount of power from other
| states (primarily Arizona and Utah, with some hydro from
| Oregon). So we essentially outsourced a lot of our power
| production to other states.
| toomuchtodo wrote:
| Arizona, Nevada, and Utah have quite a bit of area for solar
| PV. It's fine for California to import from there as long as
| they use their leverage to force a move away from coal now,
| and natural gas later. Clean hydro from the PNW is no
| different than PJM and NYISO grids importing clean nuclear
| and hydro from Ontario, Canada (which they do).
| dogsgobork wrote:
| Drawing solar from states to the east would only make the
| duck curve worse though, right? Power production would
| taper off even earlier than the peak demand.
| jedberg wrote:
| It would be made up for in the morning though when that
| solar starts producing sooner. Unless everything is
| renewable already, it could offset some non-renewables
| getting used before sunrise and allow battery charging to
| start earlier.
| toomuchtodo wrote:
| You can charge your residential or utility battery
| storage from the imported hydro or solar depending on
| spot prices, no need to consume immediately at that time.
|
| Transmission is crucial for flexibility in balancing
| generation and consumption, as well as optimizing storage
| utilization. You can also assume there will be times
| you'll throw away (curtail) clean energy as it's cheaper
| than it would've been to store and then deliver it, but
| you still need that capacity available at other times
| (seasonal variability).
| PicassoCTs wrote:
| California is at the caost, so why not just add what amounts to
| reservoir dams of the coast? Why batteries?
| potiuper wrote:
| Maybe a few decades ago, but dams have more problems than
| batteries, especially along near the ring of fire/faults. Hard
| enough to ensure proper maintenance is done in serene Michigan.
| 2Gkashmiri wrote:
| I got my "hybrid" inverter today. My panel size is 330w x 16. So
| 5.2kWh. Grid tied system. 1 year. Average production 28 kWh on a
| good day with no grid power cuts.
|
| Well the new hybrid inverter from phocus is supposed to use the
| generation when grid outside is down internally at home and that
| opens up a lot of possibilities.
|
| Been thinking about using solar water heating to reduce
| electricity consumption but that is a big project.
|
| Batteries are still expensive in india. Lithium ion is
| prohibitively expensive than lead acid. Agreed it pays in time of
| life but still.
|
| Edit: anyone know if I can incorporate phocus inverter into home
| assistant ? It has ble so some sort ?
| HPsquared wrote:
| I wonder if anyone has invented a "storage heat pump" for air
| conditioning purposes.
| toomuchtodo wrote:
| https://en.wikipedia.org/wiki/Ice_storage_air_conditioning
| nomoreplease wrote:
| Off-topic but reflecting on the PV in the domain name:
|
| What kind of home PV solar panels should a person ask a
| contractor for? How do you know they're giving you quality rated
| panels?
| octopaulus wrote:
| Reputable cells from a factory that laminates them well
| philipkglass wrote:
| Energy storage projects are typically described in terms of
| maximum power (megawatts) and hours of supply at peak power.
| Multiplying hours and megawatts gives megawatt hours, a unit of
| energy. Gigawatts and gigawatt hours are just different magnitude
| units for the same power and energy values, like meters and
| millimeters.
|
| Most electrical grids experience peak demand in the early evening
| when people come home from work, turn on lights, cook dinner,
| etc. This peak period is usually on the order of 4 hours. This
| early evening period is also when solar output drops toward zero.
|
| Energy storage projects in CA are currently generally provisioned
| for 2-4 hours of storage to ensure a good match to this daily
| evening demand peak and dropping solar output. Storage is still
| expensive so it doesn't make financial sense to add capacity that
| isn't going to be used most days.
|
| Some of these projects publish detailed information about power
| _and_ energy. Others just publicize power, but given what is
| known about the California market their energy capacity can still
| be estimated to a reasonable degree.
| danans wrote:
| > Gigawatts and gigawatt hours are just different magnitude
| units for the same quantities, like meters and millimeters.
|
| I liken it more to distance vs speed. Power, like speed, is a
| rate, in particular the instantaneous rate at which energy is
| transferred.
|
| Expressed using the same scheme we use for speed (distance per
| time : power per time), power is watt-hours per hour (or 0.0036
| megajoules per hour).
|
| I'm guessing we express power differently because James Watt
| codified the standard unit for power and the standard for
| electrical energy came from the time-integral of his definition
| of power.
| vondur wrote:
| This is what confuses many people, especially with solar and
| battery storage. "I've got 400 watts of solar feeding into my
| 400AH of batteries with a 3000w inverter" Most people will
| have no idea how much usable power they get and how much
| energy storage they need to meet their needs. (this example
| is mostly from an RV perspective)
| danans wrote:
| In general, people are not used to formally separating
| power and energy as concepts, much less as units of
| measure.
|
| This makes perfect sense because most of the measurements
| of things we own or consume are counted in units like area,
| volume, and energy, which are inherently more tangible than
| an instantaneous rate like "power". Speed is a bit of an
| exception to this, but I think that has to do with the
| ubiquity of speedometers in cars.
|
| To the extent that people broadly understand power as
| distinct from energy they tend to do so in a mechanical,
| not an electrical context, and in less precise terms
| ("That's a powerful truck"). However, some exceptions to
| this are light bulbs and electric space heaters, where
| people generally understand power as being proportional to
| brightness and heat output.
|
| In a way, it's an incredible testament to the engineering
| of electrical systems that people have been able to largely
| ignore the difference between power and energy, or just
| need to flip a circuit breaker if something exceeds a
| limit.
| Ajedi32 wrote:
| Amp hours is particularly annoying IMO because you can't
| convert it to energy without knowing the voltage.
| imtringued wrote:
| The reason that battery capacity is measured in amp hours
| is that you can't know the exact voltage of the battery
| as it drops with lower levels of charge.
| danans wrote:
| > "Ive got 400 watts of solar feeding into my 400AH of
| batteries with a 3000w inverter"
|
| Assuming 12V, that's about 400Ah*12V=4800Wh of storage.
| 4800Wh/400W = 12 hours to charge those, which seems
| reasonable for an RV. The thing that seems a bit oversized
| is the 3000W inverter.
| philipkglass wrote:
| I meant the "giga" units relative to their "mega"
| counterparts. Same physical quantities but multiplied by
| 1000.
| danans wrote:
| Hmm, in that case your comparison should be from MW to GW,
| not GW to GWh, right?
| philipkglass wrote:
| I referred to megawatts and megawatt hours in my first
| two sentences. "Gigawatts and gigawatt hours" was
| indicating counterparts to MW and MWh. Though apparently
| that grammatical construction was not as clear as I
| initially believed.
| danans wrote:
| Ah, OK. Thanks for clarifying!
| jeffbee wrote:
| Everything about these storage projects is available as public
| records from the CPUC, down to the site plan drawings.
| philipkglass wrote:
| Thanks! I've been noticing these projects mostly from press
| releases that surface through Google News, and those don't
| always provide both numbers. It's good to know that there is
| a detailed source of open data.
| kumarski wrote:
| $FCG & $TELL - I've bought heavily levered.
|
| Gonna be a gnarly market.
| ThePadawan wrote:
| Take a shot every time the article uses "GW" and "MWh/GWh"
| apparently interchangeably for "energy" or "power", also
| seemingly at random.
| renewiltord wrote:
| Actually, I thought it was very easy to understand. For
| instance,
|
| > _Fortunately, 2,000 MW of energy storage capacity is coming
| online by August 1, per the California Public Utility
| Commission. Much of this capacity will have four hours of
| battery energy sitting behind it, nearly 8,000 MWh in total._
|
| That's 2 GW of power delivery backed by 8 GWh of storage.
| Denvercoder9 wrote:
| _> 2,000 MW of energy storage capacity_
|
| I think this is where the confusion starts: if someone talks
| about "energy storage capacity", my first association is the
| amount of energy that can be stored, not the rate at which
| that energy can be discharged from the storage (i.e. power).
| samatman wrote:
| It is a bit confusing, but it isn't wrong, there are just
| two capacities in question.
|
| We could call them power capacity and energy capacity. This
| system can deliver 2000MW for four hours, or 1000MW for
| eight hours, but can't deliver 4000MW for two hours,
| because that exceeds the power capacity.
| s1artibartfast wrote:
| How is it not wrong?
|
| The battery energy storage is 8GWh with a power capacity
| of 2GW. There is no such thing as a _power storage
| capacity_ , because power is a rate. However, the storage
| may have a power capacity. pedantic, I know.
| cptskippy wrote:
| Why not call it the rate or throughput?
|
| We don't state that a car with a 100mph top speed has a
| 100mph capacity.
| [deleted]
| sib wrote:
| But then it seems that they should say "2000MW of
| delivery capacity" rather than "storage capacity"
| renewiltord wrote:
| It's not "storage capacity", it's "energy storage
| capacity". Think of it like "sources of power". Source 1
| is nuclear, Source 2 is Hydro, Source 3 is Energy
| Storage.
|
| What are our power sources available to the grid today?
| Nuclear, Hydro, Energy Storage.
|
| What are the capacities?
|
| Nuclear capacity is 1 GW
|
| Hydro capacity is 1 GW
|
| Energy storage capacity is 2 GW
| renewiltord wrote:
| Sure, but you can then read the next sentence and the
| confusion should disappear.
|
| The right answer is to use power and energy capacity
| respectively if you're talking to lay people but this
| publication is talking to people who disambiguate based off
| the units pretty easily.
|
| Nuclear capacity/wind capacity/Energy Storage Capacity.
| Three different delivery methods for power. That's how
| they'd read it at the end of the sentence.
|
| But anyway, the trick is to perform either unit
| disambiguation or perform one sentence lookahead.
|
| And finally, think of it as no different from using the
| summation convention in tensor notation. You read it and
| you're like wtf but that's because you're not the audience
| and you lack the context to get it.
| firebaze wrote:
| "My car runs 100 miles!" instead of "My car runs 100 miles per
| gallon!", and almost anyone would notice something is amiss. I
| don't get the difference to mixing "Watts" with "Watts/hour".
| pranavjoneja wrote:
| Energy is not Watts per hour (Watts/hour), it's Watts times
| hours (Watt-hours). Sorry for pedantry, but the units are the
| topic of discussion here.
| HPsquared wrote:
| That's got me trying to visualise "mile-gallons", and
| failing because its dimensions would be "length^4".
| [deleted]
| vizzier wrote:
| And in turn, watts are joules per second. Resolve Hours to
| 3600 seconds means 1 Wh = 3600 Joules. Which is the unit we
| should be using.
| [deleted]
| long_time_gone wrote:
| Not knowing the difference in miles and miles/gallon will get
| you stranded in your car pretty quickly. Now knowing the
| difference between watts and watts/hour will have almost no
| appreciable effect on your life. You flip a switch, the light
| turns on, and you get an invoice a month later.
| tohmasu wrote:
| Sure, but people writing articles on the subject should
| know better than to mix units like this.
| jonas21 wrote:
| This is only counting batteries. California has an additional 4
| GW of pumped storage capacity.
| ttul wrote:
| Did you mean GWh?
| jonas21 wrote:
| No, GW -- as in the pumped storage facilities can deliver 4
| GW of power continuously.
|
| The amount of energy that can be stored in California's
| pumped storage projects is enormous, measured in hundreds, if
| not thousands, of GWh, but that's mostly irrelevant to this
| discussion.
| kjeetgill wrote:
| > but that's mostly irrelevant to this discussion.
|
| Is it irrelevant? As another thread mentioned, how long you
| can provide that power for that for and how fast you can
| replenish capacity seems relevant for its usefulness
| buffering solar for after hours.
|
| I'm pretty unread on the energy storage situation so your
| insight or any good resources are very welcome!
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