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Show HN: Terminal dashboard that throttles my PC during peak electricity rates

WattWise is a CLI tool that monitors my workstation’s power draw using a smart plug and automatically throttles the CPU & GPUs during expensive Time-of-Use electricity periods. Built with Python, uses PID controllers for smooth transitions between power states. Works with TP-Link Kasa plugs and Home Assistant.

Quick update: Definitely wasn't expecting this to end up on the front page. I was more focused on publishing the dashboard than the power optimizer service I'm running. I'll take all the feedback into account and will open source an improved version of it soon. Appreciate all the comments!

3 days agoby naveen_k

Had a quick look through the code but I can't find where he actually throttles the PC. Anyone can point me to it?

https://github.com/naveenkul/WattWise

3 days agoby PeterStuer

If your computer is still doing bursty jobs during that period, it will use less power but still as much energy. Sure, you can reduce the power but if you aren't also reducing what you ask it to do, it'll just use that max amount of allowed power for a longer period of time.

3 days agoby russdill

Pretty neat! I’m currently working on a project that uses an ESP-C6 that just exposes a “switch” over matter/thread thats based off the results from the Spanish electricity prices API. The idea is have the switch be on when it’s one of the cheapest hours of the day, and off otherwise. Then other automations can be based on it. This was pretty trivial to do in home assistant but I want something that’s ultra low power and can just be completely independent of anything for less technical users. My end goal is to have a small battery powered device that wakes up from deep sleep once a day to check the day ahead prices via WiFi. The C6 might be overkill for this, but once I have a proof of concept working I’ll try and pick something that’s ultra low super ultra low power. Something that needs charging once or twice a year would be ideal.

The ideal form factor might be a smart plug itself, but I can’t find any with hackable firmware and also matter/thread/wifi.

3 days agoby gorbypark

Nice project, but would it not be more rational to have your system running underclocked/undervolted at the optimal perf/watt at all times, with an optional boost to max performance for a time critical task? Running it away from the optimum might save on instant consumption but increase your aggregate consumption.

3 days agoby PeterStuer

It's usually more energy-efficient to finish a task quickly with a higher power draw, also known as race-to-idle.

3 days agoby throwaway3231

Within the next year or two, I'm going to look at implementing something similar at my work.

We don't pay for electricity directly (it's included in the rackspace rental), but we could reduce our carbon footprint by adjusting the timing of batch processing, perhaps based on the carbon intensity APIs from https://app.electricitymaps.com/

Though, the first step will be to quantify the savings. I have the impression from being in the datacentre while batch jobs have started that they cause a significant increase in power use, but no numbers.

2 days agoby Symbiote

People have made valid criticisms about the basic effectiveness of your strategy. But in any case, this is a pretty awesome hacker project - nicely done! Love the appearance of your CLI tool. I am definitely bookmarking for future inspo

3 days agoby gitpusher

Wonder if a big UPS/power bank would be better? Charge it during periods where power is cheaper, and utilize it when power is more expensive. Then again if you do not need full performance all the time - this is a cool solution.

3 days agoby whalesalad

Why all this instead of a simple cronjob switching from performance to powersave profiles depeding on current time (=electricity price)?

3 days agoby ajsnigrutin

From what I’ve seen price per token make home generation uncompetitive in most countries. And that’s just on elec - never mind cost of gear

Only really makes sense for learning or super confidential info

3 days agoby Havoc

This looks cool but I feel it should notify the user with a snip from the song "You Suffer" by "Napalm Death" when throttling occurs.

2 days agoby mythrwy

Could you share how much you have saved in $?

3 days agoby gtirloni