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Re:Claude Haiku 5.5 on Wednesday October 07, 2026 @04:02PM (#49998069)
Not yet, as of version 2.1.293. But I suspect this is coming next.
To avoid these Claudisms, I asked Claude to add instructions to my AGENTS.md. The first line it added:

  Avoid the stock LLM register.
Sigh.
Unless you add battery storage, which is increasingly the case:

https://pv-magazine-usa.com/2026/02/25/solar-and-storage-to-...

> Oh, and also batteries such as the tesla power wall can only be charged and discharged about 1000 times before they have lost a lot of capacity.

Powerwall's cycle life is much better than 1000. The Powerwall warranty guarantees 70% capacity after 10 years of daily cycles (i.e. 3650 cycles). This means they expect the capacity to be substantially above 70%.

We posted an analysis of Powerwall capacity retention: https://www.netzero.energy/content/2025-02/powerwall-analysi...

Re:CO2 Battery on Friday July 25, 2025 @02:53PM (#44686858)
Ah, those are wholesale prices. And the form factor will increasingly be prismatic LFP packs, not cylindrical cells.

For buying LFP cells, I would start here: https://diysolarforum.com/

Re:CO2 Battery on Friday July 25, 2025 @01:55PM (#44686103)
Grid-scale storage (and increasingly EVs) use lithium-iron-phosphate battery cells, which don't require cobalt/nickel/manganese.
Re:CO2 Battery on Friday July 25, 2025 @01:44PM (#44685974)
I think 12 years is an underestimate. Lithium-ion batteries will degrade, but they still have usable capacity. There are Tesla Roadsters still going strong, 15 years in. And the battery cell chemistry has since shifted to LFP, which has longer cycle life.
Re:Aluminum Batteries Outlive Lithium-Ion with a Pinch of Salt on Thursday February 06, 2025 @03:37PM (#42966247)
You can't really generalize cycles based on chemistry alone. Battery management and usage matters. But two examples with NCA/NMC chemistry:

- The Tesla Powerwall 2 battery warranty[1] is for effectively 3650 cycles (daily cycle for 10 years).

- Many cases of Tesla cars at 200k mileage (~1000 cycles, depends on battery size) with less than 15% capacity loss[2].

And these batteries didn't die after reaching the high number of cycles, they just retained less capacity.

[1] https://energylibrary.tesla.com/docs/Public/EnergyStorage/Po...

[2] https://insideevs.com/news/723734/tesla-model-3y-battery-cap...

Re:Geothermal Power in the North Bay – Jon Udell on Thursday October 10, 2024 @07:56PM (#41804777)
> It accounts for 20% of California’s renewable energy.

That doesn't sound right. It seems to come from Wikipedia with a 2019 date, but even then:

The Geysers produced 5,543 GWh in 2022 [1].

California generation from renewables:

2019: 64,336 GWh [2]

2023: 76,153 GWh [3]

[1] https://geysers.com/The-Geysers/Geysers-By-The-Numbers

[2] https://www.energy.ca.gov/data-reports/energy-almanac/califo...

[3] https://www.energy.ca.gov/data-reports/energy-almanac/califo...

Re:Can solar costs keep shrinking? on Thursday August 29, 2024 @03:19PM (#41394366)
We need all the renewables we can get, and I think you can have both -- utility-scale and rooftop. Rooftop solar (and battery storage) just needs to be cost efficient to offset the rising cost of electricity and make it a good return on investment.

The "attacks on net metering" are merely acknowledging that the proportion of renewables on the grid is high enough that balancing grid supply and demand is becoming an issue. I'm a big proponent of rooftop solar, but the reality is that 1:1 net metering just doesn't make sense once there's a critical mass of solar installed (the duck curve problem). This is not a problem unique to California or the US. If you look at other places with high solar adoption (Australia, EU), you'll find even stricter policies like negative feed-in tariffs: the utility will charge you for exporting solar to the grid.

Battery storage is a solution to that problem, but that's where prices are still too high. I'm actually surprised that battery storage is not mentioned in the article, because that's a critical component of allowing solar/wind to grow further.

Re:Breaking down a record-setting day on the Texas grid on Thursday August 22, 2024 @01:49AM (#41317214)
I agree about home batteries being too expensive, hopefully prices will come down with scale.

But the part about battery degradation is not true. Tesla Powerwall has a 10 year warranty[1] with 70% capacity retention. This means that Tesla has data showing that the battery will have higher capacity than 70% after those years. That's a lot of cycles and a lot of renewable energy that the battery will provide in its lifetime.

[1] https://energylibrary.tesla.com/docs/Public/EnergyStorage/Po...

Dynamic tariffs (aka real-time or wholesale plans) are becoming more common in the UK an EU. These are usually priced by 30-min periods and announced 24h in advance. More modern utilities will offer apps that control when your car is charged (in exchange for cheaper rates). But I agree, optimizing this is fun too. I'm building support for configuring Tesla Powerwall systems based on dynamic tariffs.

If you have the option, the best time to charge your car would be during the day when there is abundant solar.

Re:Ask HN: What apps have you created for your own use? on Wednesday December 13, 2023 @10:30AM (#38628805)
I wanted a better dashboard for my Tesla solar/battery system: https://www.netzeroapp.io/
Re:The Next Power Plant Is on the Roof and in the Basement on Tuesday November 21, 2023 @02:35AM (#38360533)
PVWatts is a good resource to estimate solar production based on location, system size, roof orientation, etc:

https://pvwatts.nrel.gov/pvwatts.php

Re:The Next Power Plant Is on the Roof and in the Basement on Tuesday November 21, 2023 @02:31AM (#38360503)
Tesla Powerwall is probably the most commercially successful home battery. It comes with a warranty guaranteeing 70% capacity after 10 years, which is not to say it has a 10 year lifetime. It's still early to determine its actual lifetime, but the battery technology is also rapidly improving due to the EV transition.
Re:The Next Power Plant Is on the Roof and in the Basement on Tuesday November 21, 2023 @02:03AM (#38360332)
Lots of variables in sizing a battery system:

- Is your goal battery backup or load shifting?

- How much backup do you need?

- What is your energy usage and peak demand during that time?

Peak demand is a big factor: a single Tesla Powerwall 2 for example has 13.5 kWh of capacity but only 5kW of continuous power. A heat pump or AC can exceed that, which is why many people stack multiple batteries to be able to power their homes. (The new Powerwall 3 can supply more power.)

Re:The Next Power Plant Is on the Roof and in the Basement on Tuesday November 21, 2023 @12:39AM (#38359804)
In case your system is from Tesla: I wrote an app that you can load on a tablet and stare at that energy flow all day :)

https://www.netzeroapp.io

Re:What Is Dbt and Why Are Companies Using It? on Thursday December 02, 2021 @10:20PM (#29426281)
The dbt community will frequently run Snowflake, and its SQL engine is very good.

https://medium.com/@jthandy/how-compatible-are-redshift-and-...

I had the same problem and built this: https://zigam.github.io/ginkgo/
Re:MixedName – Bilingual baby name finder on Wednesday August 26, 2020 @04:49PM (#24287116)
Also did something similar and generalized it across languages by using Metaphone phonetic encoding (which is biased towards English pronunciation however):

https://github.com/zigam/ginkgo/blob/gh-pages/README.md

43% according to NYT (includes residents and workers): https://www.nytimes.com/interactive/2020/us/coronavirus-nurs...

55k+ deaths, 296k+ cases, staggering numbers. Out of a 1.3M nursing home population (https://www.cdc.gov/nchs/fastats/nursing-home-care.htm), which makes you wonder if the recent decrease in deaths is driven by the fact that the majority of the susceptible nursing home population has already been affected.

Re:The tricky math of Covid-19 herd immunity on Saturday July 04, 2020 @05:40PM (#23735088)
> Less than 1% of the US population is confirmed to have contracted the virus

CDC estimates based on seroprevalence data that for every case reported there are actually 10 other infections: https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/comm...

Re:Covid-19: The T Cell Story on Wednesday June 17, 2020 @06:50PM (#23557748)
Imperial College report showing mobility trends explain over 80% of observed variations in transmission:

https://www.imperial.ac.uk/media/imperial-college/medicine/m...

Re:Covid-19: The T Cell Story on Wednesday June 17, 2020 @06:36PM (#23557627)
Re:Simple Personal Finance Tracking with GnuCash on Tuesday May 19, 2020 @06:37PM (#23241131)
https://www.firecalc.com/ is a good retirement calculator.
In this study they tracked 104 patients from the cruise ship, from Feb 11 to Feb 25. Started with 43 asymptomatic (41%), went down to 33 asymptomatic (32%).

https://www.medrxiv.org/content/10.1101/2020.03.18.20038125v...

Re:We’re Testing the Wrong People on Thursday April 23, 2020 @12:16PM (#22957556)
Here’s a paper from the Broad Institute: https://www.biorxiv.org/content/10.1101/2020.04.06.025635v1
Re:A (possible) solution to Covid-19 on Friday April 10, 2020 @03:41AM (#22830872)
> More than 50% of the people infected with SARS-CoV-19 are asymptomatic (i.e. they have no illness).

Note: asymptomatic at the time of testing. They may still develop symptoms over time.

https://www.icelandreview.com/sci-tech/is-icelands-coronavir...

https://twitter.com/cmyeaton/status/1246196001775460358

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