Path: news.eternal-september.org!eternal-september.org!.POSTED!not-for-mail From: Don Y Newsgroups: sci.electronics.design Subject: Re: A research team has managed to coordinate 100 domestic air conditioners to stabilise the power grid in real time, as if they were a flexible power plant. Date: Sun, 15 Jun 2025 14:39:41 -0700 Organization: A noiseless patient Spider Lines: 40 Message-ID: <102neiu$1551j$1@dont-email.me> References: <8790ilx0bl.ln2@Telcontar.valinor> <596r4k98hrbr3j5brdk3oe8rq7rdmvcing@4ax.com> <102ke8c$bdv0$1@dont-email.me> <102kt5d$dhhl$3@dont-email.me> <102lvra$pum5$1@dont-email.me> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Injection-Date: Sun, 15 Jun 2025 23:39:45 +0200 (CEST) Injection-Info: dont-email.me; posting-host="3636aa95eb15079f6961878d00147f92"; logging-data="1217587"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX19reN7oEHZqrkOOqKJOOx7r" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:/gnpDh1DVnR/6/LaiCu26krL2yw= Content-Language: en-US In-Reply-To: <102lvra$pum5$1@dont-email.me> On 6/15/2025 1:22 AM, Don Y wrote: > On 6/15/2025 12:40 AM, Carlos E.R. wrote: >> On 2025-06-15 00:29, Don Y wrote: >>> On 6/14/2025 2:53 PM, Carlos E.R. wrote: >>>> That's not what they are doing. They are changing the load in tiny parts of >>>> the cycle, 50 or 60 times per second. Changing the load waveform. >>> >>> No, they are deferring the start of the compressor and/or blower. >> >> I understand they are adjusting the frequency. > > "The air conditioners were connected to control boards capable of modifying > the on/off cycle of the compressor depending on the frequency of the grid." > > I.e., deciding when the compressor would run and when it would NOT run. > E.g., They aren't talking about using VFDs for the compressors. > Rather, they are trying to alter when compressors are engaged to better > balance the load so a given "supply" can remain more constant. > > [The frequency of the supply varies depending on how outsized the > load happens to be at any given point in time] Here's the original paper: In their description of the hardware, you can see that they simply bodged the role of the thermostat to force the compressor on/off per *their* dictates instead of letting it simply track the interior temperature of the edifice. >> My AC doesn't have a thermostat, > > Then how does it know when to run and not run? > >> it is continuously adjusted in tiny power adjustments with an inverter. >> Switching a thermostat on/off would destroy it. > > So, in winter, it still cools? > >