From owner-freebsd-chat@freebsd.org Sat Nov 21 21:53:50 2020 Return-Path: Delivered-To: freebsd-chat@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 899C4471D8C for ; Sat, 21 Nov 2020 21:53:50 +0000 (UTC) (envelope-from rwmaillists@googlemail.com) Received: from mail-wm1-x336.google.com (mail-wm1-x336.google.com [IPv6:2a00:1450:4864:20::336]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "smtp.gmail.com", Issuer "GTS CA 1O1" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4CdnHK4XNXz3hYg for ; Sat, 21 Nov 2020 21:53:49 +0000 (UTC) (envelope-from rwmaillists@googlemail.com) Received: by mail-wm1-x336.google.com with SMTP id a65so13750366wme.1 for ; Sat, 21 Nov 2020 13:53:49 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=Mt/Vr8asGDmepngqCXeLGnkhUBR8WOmSQ0G/LvRFkiY=; b=GTYRPelkovr4zzmPmMPughpo9ztZZRoMVfpQ66bTVHRVQXx4u4MM1o7hP9UcLVljn6 1WEfTNb/MlEFXBPD01aJx3jcnaMqXL1ISTIch5ID7Cy9vyRZxTJXunbmbxUGQTWD5dqQ 8cnD4kqDPgPCJ5QQxOzVXBx+2rFOjvfrlwm3VXOgncctjDeKgEitiKRs2ev7WeWxDe19 KeML4HNm/yL3pEnGKZZpu91HeRQv/oTmOn6HQCGaQnKCrUF+/Z3S8n6CcoTKqv/OAxHr zH3Ju2GCNTeo60zjT4kK+qH1alxANaO8jUY3iPdaWotkKPJ6CIY2bxoCRVHK+rb4RlTR H5ww== X-Gm-Message-State: AOAM530zXCzNepyYS1We8JZn8zgh0UF0LHar17jCGoAwjWTyUCqOS9+1 KEZpKkNV4/Js/AYSJH5sPcrlaq0iXfM1/w== X-Google-Smtp-Source: ABdhPJwmSrBV8Xp0ehgJWVey4R3XTlI4Ig5U5BJ+nlNoFJbaTp7kP4TRDfJByXwvahPJsFpQ9vnEWw== X-Received: by 2002:a1c:5605:: with SMTP id k5mr15461094wmb.99.1605995627441; Sat, 21 Nov 2020 13:53:47 -0800 (PST) Received: from gumby.homeunix.com ([2.220.20.221]) by smtp.gmail.com with ESMTPSA id w10sm10584794wra.34.2020.11.21.13.53.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 21 Nov 2020 13:53:46 -0800 (PST) Date: Sat, 21 Nov 2020 21:53:42 +0000 From: RW To: freebsd-chat@freebsd.org Cc: Ralf Mardorf Subject: Re: Sustainability of switching power supplies Message-ID: <20201121215342.51bd59d9@gumby.homeunix.com> In-Reply-To: <20201121092444.2355c5a7@utnubu> References: <20201121092444.2355c5a7@utnubu> X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; amd64-portbld-freebsd12.1) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4CdnHK4XNXz3hYg X-Spamd-Bar: --- X-Spamd-Result: default: False [-4.00 / 15.00]; RCVD_VIA_SMTP_AUTH(0.00)[]; TO_DN_SOME(0.00)[]; FREEMAIL_FROM(0.00)[googlemail.com]; R_SPF_ALLOW(-0.20)[+ip6:2a00:1450:4000::/36]; RCVD_COUNT_THREE(0.00)[3]; DKIM_TRACE(0.00)[googlemail.com:+]; RCPT_COUNT_TWO(0.00)[2]; DMARC_POLICY_ALLOW(-0.50)[googlemail.com,quarantine]; NEURAL_HAM_SHORT(-1.00)[-1.000]; RECEIVED_SPAMHAUS_PBL(0.00)[2.220.20.221:received]; FROM_EQ_ENVFROM(0.00)[]; RBL_DBL_DONT_QUERY_IPS(0.00)[2a00:1450:4864:20::336:from]; FREEMAIL_ENVFROM(0.00)[googlemail.com]; ASN(0.00)[asn:15169, ipnet:2a00:1450::/32, country:US]; DWL_DNSWL_NONE(0.00)[googlemail.com:dkim]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[googlemail.com:s=20161025]; FROM_HAS_DN(0.00)[]; NEURAL_HAM_LONG(-1.00)[-1.000]; MIME_GOOD(-0.10)[text/plain]; PREVIOUSLY_DELIVERED(0.00)[freebsd-chat@freebsd.org]; SPAMHAUS_ZRD(0.00)[2a00:1450:4864:20::336:from:127.0.2.255]; TO_MATCH_ENVRCPT_SOME(0.00)[]; RCVD_IN_DNSWL_NONE(0.00)[2a00:1450:4864:20::336:from]; MIME_TRACE(0.00)[0:+]; FREEMAIL_CC(0.00)[zoho.com]; RCVD_TLS_ALL(0.00)[]; MAILMAN_DEST(0.00)[freebsd-chat] X-BeenThere: freebsd-chat@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Non technical items related to the community List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 21 Nov 2020 21:53:50 -0000 On Sat, 21 Nov 2020 09:24:44 +0100 Ralf Mardorf via freebsd-chat wrote: > Hi, > > does anybody know about papers related to the sustainability of > switching power supplies? > > In my very limited experiences they are seemingly less sustainable > than old school power supplies. > > I'm curious, if any paper does exist related to energy efficiency of > usage of a power supply, but also taking into account how much energy > is needed to repair or replace those switching thingies and classic > stone age power supplies. In theory the difference in losses can be huge. You can see this more starkly with audio power amplification. Linear amplifiers typically have big transistors bolted to big heatsinks. Switched amplifiers may just use a small plastic chip with no heatsink at all. In practice the typical switched computer supply is not hugely efficient, but it there's a significant advantage that it's easy to build them with a near perfect power-factor. This doesn't much matter in the home, but commercial electricity customers pay extra for a poor power-factor because it would create higher losses in the the supply network if not compensated. I think that meeting power-factor regulations was the main reason for the switch. > My experiences with modern computer power supplies aren't bad, but > my impression about switching power supplies in almost everything and > the sustainability of this approach ... voltage undersized caps etc. > isn't good. Generally things are getting less over-engineered than they used to be. One problem with linear supplies is that they tend to have much larger smoothing capacitors and so contain more corrosive liquid to drip onto a more expensive circuit board.