California taking the lead again, in this case, for more widespread renewable energy production...

[JohnRBaker]

California becomes the first state to require new residential construction to include renewable energy sources:

California to require solar panels on most new homes

It's the first state where the renewable energy is mandatory.

https://www.engadget.com/2018/05/06/california-to-require-solar-panels-on-most-new-homes/

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[JStephen]

And, in a related story, I was just reading about the issues they have with so many homeless people because they can't afford houses any more.

That reminds me- when we lived in Colorado, we had a wood-burning fireplace insert- only the local governments limited when it could be used- so they actually limited use of renewable energy there. Bet they still do, for that matter.

 

[dgallup]

When I used to ski in New England I would curse the home owners and their wood burning stoves. All the valley air would be thick with smoke, horrible.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

 

[zdas04]

And this is a good thing, why?

The "expected 25 year life" is an absolute myth. The panels lose (on average) 4% of their nameplate capacity every year due to sand blasting, dirt accumulation, and minor electrical short and open circuits. 4% per year times 25 years equals 100%. So for the last 5-10 years of "life" the panels generate something on the order of 2% (and declining) of their nameplate power and the $50-60k operating savings is much closer to $10-20k for a $25-30k investment or basically never recovering their capital. As to the Tesla Powerwall, they haven't been around long enough to know how they will perform over time or what the inevitable unintended consequences will be.

Even if the panels did last for 25 years, and even if they did offset an average of $50k in electric costs spread evenly over that time period (i.e., $2000/year), the project's rate of return is under 4%. If we assume that the cost of electricity goes up faster than the capacity of the panels goes down (i.e., year one avoided electricity is $3846 and year 25 avoided electricity is $153) then the rate of return goes up to 7% which is not a rate that would attract investors.

This is yet another horrible idea foisted on the citizens of California (those who do not choose to flee to Texas before this goes into effect) that will never pay for itself and never do a single good thing for the environment.

[bold]David Simpson, PE[/bold]
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist

 

[MintJulep]

Just how expensive is electricity in CA?

My annual electricity cost is about $650.

Not sure how I could save $2000 annually.

 

[JohnRBaker]

Our electric bill for 2017 totaled $1,253.36, which is probably less than average as we've already taken a lot of steps to control costs, including high-efficiency appliances, high-efficiency A/C, 98% LED lighting, etc.

As for this year, thru April, we're running about the same as last year.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[zdas04]

OK, how do you save $2k off of a $1,253.36 bill? Same question as MintJulep's, just with different numbers. Average residential electric costs in CA are $0.152/kWh (national average is a bit under $0.11/kWh). An average home uses 908 kWh/month. Using averages, you get $1656/year. How do you reduce that by $2k? Are the post-2020 houses going to be less energy efficient than your home with all of its retrofitted controls (and I would bet you a lot of money that my whole-house swamp cooler which uses about 43 kWh per month is using a LOT less power than your high-efficiency air conditioner)?

[bold]David Simpson, PE[/bold]
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist

 

[JohnRBaker]

I'm not planning to install solar panels on my home (however, our middle son has them on his house up in LA). We looked into it a couple of years ago but couldn't justify the cost. Besides, my homeowner's association officially won't approve them. That being said, a neighbor down the street installed them and when the HOA complained, he had his lawyer send them a letter saying basically "sue me". He's never heard anything back and that was over a year ago.

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[hokie66]

Sounds to me like California is marching to the rear, again. We have a couple of states in Australia intent on relying on "renewables", and instead, they are quickly relying on coal fired generation from neighboring states.

 

[davidbeach]

If it loses 4% per year, after 25 years there’s about 36% of the original capacity left. 0.96^25

 

[zdas04]

davidbeach,
What I said was (emphasis added):

The panels lose (on average) 4% of their nameplate capacity every year

I was pretty careful to say "of their nameplate capacity" (a constant value established by the manufacturer) not "of their remaining capacity." It is a good idea to read a post before you start snarking at it.

[bold]David Simpson, PE[/bold]
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist

 

[GregLocock]

If they were serious about pV they'd use solar farms, not rooftop systems. The advantage of rooftop systems is that to some extent it reduces the load on the network, as some power gets used locally. In California I imagine the daily load profile in summer is much like in Oz,peaks at around 3pm, as everyone's A/C picks up, more or less in sync with solar. The problem is that large modern residential districts will act as mini power stations when that happens, and the distribution network is not designed to handle that. I see up to 270V on a nominal 240 V supply locally as the rooftop pVs drive the grid. Psychologically rooftop solar may be an easy way of getting the long suffering punter to personally stump up for batteries, increasing the resilience of the system overall at little cost to the main generators of power.

As a matter of interst

(a) is the Californian grid basically a monolith?

(B) what's the typical split between fossil fuel, local pV, local wind, nuclear and out of state sourced energy? What is the breakdown for the out of state supply?

In South Australia they claim about 50% renewable, mostly wind. The rest is natural gas, or diesel, as they closed down their last coal plant a couple of years back. On a sunny day that is windless I have seen renewables in SA down to 1% of the total requirement, so they are entirely reliant on the interstate connectors, ie coal, to make up the slack.




Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[hokie66]

Amen, Greg. I agree with solar farms, and a lot of them are going ahead. But you need to use land which is of limited value for other purposes. When Japan closed all its nuclear plants, they frantically planted solar farms on productive agricultural land. This exacerbated their inability to feed the population.

 

[GregLocock]

Here in a timely fashion, are two relevant papers

The first discusses the reduced value you get for adding more renewables (other than nukes, tidal or hydro presumably) to the grid

https://www.neon-energie.de/Hirth-2...wables-Solar-Wind-Power-Variability-Price.pdf

And here's 68 pages of NY state electricity people's current ideas about a 50% RET

http://www.nyiso.com/public/webdocs...wer_Trends/Power_Trends/2018-Power-Trends.pdf

Between the two I think that without a thorough rethink and a lot of money, a RET above 20% (particularly wind) is a rolling ongoing potential disaster.

Sadly the NY paper includes the ludicrous V2G idea without laughing at it. Using my very expensive car to prop up the grid rather than a genny or a nice big stationary battery is daft.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[moltenmetal]

I'm a huge EV advocate and even I see "V2G" as completely dumbass. Nobody who is advocating it has seriously thought about it in my opinion. Most of the advocates either imagine DC/AC conversion capacity in every car that doesn't in fact exist (or worse still, they imagine direct DC charging capacity in every parking space that will NEVER exist...). Then there's the shell game that's played to avoid paying EV owners the real value of energy stored in their onboard packs- they claim that the EV owner will get a benefit because they'll keep their battery at lower SOC throughout the day and hence magically get the ability to cycle their battery without actually leading to additional degradation. Of course the obvious alternative for the EV owner would be to just stay away from high SOC in the first place if they don't need the extra capacity...

There is something much simpler and cheaper and more efficient than V2G, though: opportunity charging based on price, combined with EVSE control by the grid operator. In return for a board in each Level 2 EVSE and a little software, the EV owner can agree to accept an "opportunity charge" at a pre-arranged price, under the control of the grid operator. The grid operator would then have access to enormous switchable demand, at a cost lower than what it cost them to do the same thing with my air conditioner at home (which they did, in a program called PeakSaver). This doesn't generate unnecessary battery cycling with inherent losses and costs in terms of battery degradation.

As far as grid storage, several bits of low hanging fruit seem to be around: one is using hydro dams to do more modulation than baseload (within the limits of what people will tolerate in terms of reservoir level and river flow fluctuation of course), and the other is flow batteries. Li ion's cycle life is still too small for it to be a good candidate for mass grid storage, but vanadium flow batteries on the other hand- more storage is just more electrolyte in plastic tanks, and if a membrane or electrode goes bad, you don't have to scrap the entire unit to replace it like you must with Li ion- they come apart rather like a plate and frame heat exchanger. Too low an energy density for vehicle applications, but for grid applications the energy density is PLENTY high enough, and the efficiency is way higher than many other schemes. That a battery optimized for energy density above all else (i.e. Li ion) would be the best fit for something that doesn't care much about energy density is a bit of a bizarre notion to me.

 

[zdas04]

moltenmetal,
I've been wanting to talk to a "huge EV advocate" about one thing. Transportation is typically 70% of a nation's energy demand. EV's make up something under 0.1% of current transportation capacity. Getting to 100% EV would require increasing generating capacity about 4 fold (combining current shortages with replacing obsolete plants and the added transportation load to the power grid). Let's say that we somehow manage that magnitude of growth and approach it as interconnected microgrids or some other smart configuration. So now we are replacing/reconfiguring the national power grid along with building 4 times as much generating capacity as we have today. Call it $100 trillion in up front capital (based on historical capital cost/MW, with a boom in construction the costs always significantly exceed historical averages, call it $200 trillion) just for the U.S. Then you have to build a fueling/recharging infrastructure (to say nothing of the storage issues you raised).

I agree that the V2G schemes have a number of assumptions that don't stand up to scrutiny--one that I don't see any way around is that every component in the process has less than 100% mechanical/electrical/thermal efficiency so the vehicle will have to take on more power than it needs to propel the vehicle and run the bluetooth. How does that energy balance work when you will typically be supplying the grid in the morning when the grid doesn't need it and replacing the power in the onboard storage in the afternoon when the grid is ramping up for the evening heavy load. That all sounds line "engineering by wishful thinking" to me.

Without building the generating capacity, a breakneck charge to EV can't be anything but a disaster. Between capital acquisition, engineering, permitting, procurement, and construction, you are probably looking at 15 years to double capacity, so maybe 45 years to reach the required capacity? Do you see any path that holds the public's attention for 45 years (or even 15 years), and attracts several hundred trillion dollars in new capital to just the developed countries?

[bold]David Simpson, PE[/bold]
MuleShoe Engineering

In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist

 

[GregLocock]

David, where do you get 70%? That is a lot.

this says 29%

https://www.eia.gov/energyexplained/index.php?page=us_energy_use

Their graphs are in the very handy units of quadrillion BTUs. I've just found out that BTU is about 1 kJ

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[JohnRBaker]

I think you will find that the biggest user of energy is actually infrastructure, which includes factories, commercial buildings, process plants, street lighting, etc. At least that was what I was told by a guy from Siemens who worked in that part of the company that dealt with building automation and public lighting (I guess he could have been biased but Siemens has been doing this sort of stuff for a LONG time).

John R. Baker, P.E. (ret)
EX-Product 'Evangelist'
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[hokie66]

John,
I don't like that definition of infrastructure.

Based on the chart Greg linked, I would simplify it by saying 30% transportation, 30% industry, 20% commercial, 20% residential. I can remember it that way.

Note that, as explained, this is both primary and secondary (electricity) energy. And it is for the US.

 

[GregLocock]

I'm hoping it includes all energy use, not just electrickery.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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