Repost please: $1/watt solar panals.
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From: Josepi on 29 Oct 2009 09:38 Somebody has to take one "for the team" "vaughn" <vaughnsimonHATESSPAM(a)gmail.FAKE.com> wrote in message news:hc9ekp$62m$1(a)news.eternal-september.org... > > Yes, but demand, and the competition that demand generates, is a main > driver for improving technology. If we just fold our arms and wait for > technology to improve in the absence of demand, technology improvement is > unlikely to ever happen. > > Vaughn >
From: vaughn on 29 Oct 2009 09:44 "Paul Keinanen" <keinanen(a)sci.fi> wrote in message news:t15je595rkli69ea8kvac2r4utphpjrl4s(a)4ax.com... > On Thu, 29 Oct 2009 08:12:41 -0400, "vaughn" > <vaughnsimonHATESSPAM(a)gmail.FAKE.com> wrote: > >> >><nospam(a)nevis.com> wrote in message news:4ae8ff39$1(a)news.x-privat.org... >>> For a laptop, printer and a couple of 15 watt compact florescent lights? >>> Hardly a huge expense, with 1000watt inverters $100.00 on ebay, a couple >>> of Sams' club deep cycle batteries ? >> >> Actually for system you don't really need inverters at all. I use >>12-volt compact florescent lamps, > > Which definitely contains an inverter, thus, adding cost. Actually, the 120 or 240 versions also contain electronics, which also adds cost. That said, the 12-volt bulbs do cost more, mainly because they are a specialty item. > >>and 12 volt adapters are available for >>laptops. > > Which possibly also contains an inverter to convert 12 V to 17 V. Perhaps, but it would be an inverter sized for the specific job and would only be on and taking power when plugged in, (which in the case of a laptop could be rarely) > > This is a good strategy if the 12 V system total cost is less than the > cost of more common 120 V (US) or 230 V (Europe) systems added with > the inverter cost. I do it mostly to avoid the 24/7 drain of a central inverter. (Yes, I know that some inverters have power sensing, but they have their own issues.) With or without the inverter, I would still want a separate, protected power system, so that cost falls out of the equation. The outdoor lighting part of my wiring system is inexpensive because it uses common low-voltage Malibu lighting cable that is made just for that purpose. Inside my home I wire to code, so the expense is comparable either way. That leaves me with the option of converting any circuit to mains power in the future.. Vaughn Vaughn
From: Martin Brown on 29 Oct 2009 09:46 Paul Keinanen wrote: > On Thu, 29 Oct 2009 08:12:41 -0400, "vaughn" > <vaughnsimonHATESSPAM(a)gmail.FAKE.com> wrote: > >> <nospam(a)nevis.com> wrote in message news:4ae8ff39$1(a)news.x-privat.org... >>> For a laptop, printer and a couple of 15 watt compact florescent lights? >>> Hardly a huge expense, with 1000watt inverters $100.00 on ebay, a couple >>> of Sams' club deep cycle batteries ? >> Actually for system you don't really need inverters at all. I use >> 12-volt compact florescent lamps, > > Which definitely contains an inverter, thus, adding cost. Although they are cheaply mass produced as emergency standby lights. And pure solid state LED based units are still more expensive. > >> I use the lamps out in my yard, and my in-home 12-volt wiring >> system is slowly growing. > > This is a good strategy if the 12 V system total cost is less than the > cost of more common 120 V (US) or 230 V (Europe) systems added with > the inverter cost. Although you really need to pay attention to the current flowing in a low voltage DC wiring system. It takes a lot more of a percentage when you drop half a volt off 12v than the same drop on 120 or 240v. And to deliver the same power into the load takes 10x or 20x the current on a 12v service. Useful if you are off grid but not so good in winter at my latitude. Not enough winter sun to keep things topped up. Wind power is a bit better in that respect if you have the space. Regards, Martin Brown
From: wmbjkREMOVE on 29 Oct 2009 10:39 On Thu, 29 Oct 2009 09:31:53 -0400, "Josepi" <JRM(a)invalid..com> wrote: >Ten years from batteries? Not if you actually used them and didn't just >keep them on float. > >I have heard this story over and over from manufacturers but I have not >heard of anybody, actually using their batteries and discharging them each >night to a resonable level, that gets more than a few years of dependable >usage out of them. My batteries are 14 years old and still going strong. There's a pretty good chance they'll make 20, which is their nominal lifetime rating. They're the bare minimum size in the context of my consumption - generally between 12 and 15kWh per day. Only a fraction of that makes a trip through the batteries, which is as it should be for any well-managed setup. Wayne
From: Michael A. Terrell on 29 Oct 2009 10:44
nospam(a)nevis.com wrote: > > Michael A. Terrell wrote: > > > > What guarantee do you have that the seller will be in business next > > year, let alone 15 years from now? > > And the sun could snuff out tomorrow, life is chancy. With your > viewpoint we'd all still be huddled around the fire afraid of > the dark. There are no 100% guarantees about anything but your own > mortality. Yawn. I built a 48 VDC powered KU band communications system for the International Space Station while working at Microdyne. Lockheed-Martin packaged it into one of the custom rack modules and supplied the modified remote control software to NASA. It was a modifed Microdyne '700 Series' design. Cheap and long life just don't go together on batteries. If someone actually did discover how to do it, they would own the market in a very short time. Huddle all you want, around your jury-rigged toys. As far as the fire, you might get that from you overloaded and under designed 12 volt wiring. -- The movie 'Deliverance' isn't a documentary! |