Hello all. Something going through my mind while down while recovering from a bad flu. With more and more electronic small devices and lighting using the USB bus 5v, let's have a discussion thread about this and especially the Tiny-home lifestyle. I am currently doing renovations on a tiny home and I have a houseboat build coming up after that, so for me, it is a good time to explore this topic and taking as many things off the grid as possible
The standard way here in QLD is to run a roof full of solar panels, and it's all plugged into the grid. I am thinking a more modular and small factor implementations instead as a more DIY friendly approach and lessening the reliance on professional implantation and avoiding the 250v mains house supply all together and sticking to 5v as the base power. The approach that I want to personally explore is getting individual small items to run off dedicated powerbanks that have their own dedicated little solar panels, enough to always keep the bank topped up
I wonder how much of my audio, electronic, household and tools can I get running of their own self-sustaining supplies like this. I feel the merits of such an approach would be the ability to slowly grow a complete, reliable system where everything can be individually managed, tuned and replaced without affecting others. Some of my devices need plug packs in the 9 to 18v range, and I am thinking of using boost converters to the 5v powerbanks
I have been using a small powerbank over the last two years to run a small LED desk lamp and haven't noticed any problems and looks like this will run for some years yet. Only needs an hour charge once a month or so. So why not replicate it to other things around the house?
The standard way here in QLD is to run a roof full of solar panels, and it's all plugged into the grid. I am thinking a more modular and small factor implementations instead as a more DIY friendly approach and lessening the reliance on professional implantation and avoiding the 250v mains house supply all together and sticking to 5v as the base power. The approach that I want to personally explore is getting individual small items to run off dedicated powerbanks that have their own dedicated little solar panels, enough to always keep the bank topped up
I wonder how much of my audio, electronic, household and tools can I get running of their own self-sustaining supplies like this. I feel the merits of such an approach would be the ability to slowly grow a complete, reliable system where everything can be individually managed, tuned and replaced without affecting others. Some of my devices need plug packs in the 9 to 18v range, and I am thinking of using boost converters to the 5v powerbanks
I have been using a small powerbank over the last two years to run a small LED desk lamp and haven't noticed any problems and looks like this will run for some years yet. Only needs an hour charge once a month or so. So why not replicate it to other things around the house?
How do the car audio amplifier's then avoid this problem to convert 12v DC to a usable voltage internally? Is there no means to address the noise on the 5v up conversion?
They do have noise, but also filters. Look at some of the SMPS threads here discussing noise.
Every situation will be somewhat unique, though.
Every situation will be somewhat unique, though.
Wire size might be an expense to consider, 16 AWG wire is only rated at 15 amps, 75W 5v. To run a 750W toaster
you would need 3 AWG.
https://www.engineeringtoolbox.com/wire-gauges-d_419.html
you would need 3 AWG.
https://www.engineeringtoolbox.com/wire-gauges-d_419.html
I'm the designer of the SMPS DC filter sold in the diyAudio Store, (link). It's optimized for line level applications, where the gear being powered needs a maximum of 48V DC and a DC current of 3A max. Its circuit topology is a series filter, which requires physically small components that are inexpensive. However series filters are only practical for low current applications; if you want high power (100 watts?) at 5 volts, that's 20 amps and you have very little choice but to abandon series filters & use parallel filters instead. Regrettably, SMPS DC parallel filters use physically large components that weigh a lot and cost a lot. You won't ever find a 20 ampere SMPS filter kit-of-all-parts in the diyAudio Store for ten dollars, I'm afraid.
USB is not 5V anymore. Latest high-power devices such as phone chargers and laptop power supplies use a USB-C feature to negotiate a higher voltage. The most common charging voltage for today smartphones is 12V and for laptops is 19V. Voltages up to 48V on USB connector are planned. The search keyword for cheap DIY boards with a USB-C power chip that can be set to any voltage supported by modern chargers is "PD trigger". A few expensive power banks also have an auxiliary output jack that can be set to any supported voltage manually, saving the expense for a separate trigger board.
Surveying all my stuff, most items are already either made for USB bus power or have a switch between power options that include the USB port at the power input on the back. That leaves things like the 65" tv, Roland and Yamaha mixers and the tube preamps which are not bus powered but have a mains cord/plug. But see my reply to pcan
My stuff is also heavily 12v based, especially for the houseboat as that will be running 12v motors, solar and turbine backed up by a diesel generator. I am not set on 5v as base and also considering a 12v base system with inverters for things that only have a mains cord
Good to know about the higher voltages with USB-C, I hadn't caught on to that as I only have a couple of items, and they have the USB-C on the item side and standard USB 3 on the PC side. This still only helps the case by case approach that I am thinking of adopting into my renovations. Would I be guessing correctly then that all the items made to run off any of the USB bus voltages will be fine connected to an appropriate powerbank, case by case?
And the 240v cord items on their own 12v with inverter network
That leaves auto top-up of the powerbanks using solar+turbine+gen set. Is it actually feasible to run a powerbank in a car type always on battery/charger/load combination? I mean, charge always coming in from either solar or wind into the powerbank while it's hooked up to the drain gear?
If you will be using small amplifiers too then 5V is not the right voltage. With 12V a lot more is possible as one can use car stuff. In the past I did such a project for someone that wanted to live off grid. Then it was impossible to find decent/efficient 12V refrigerators, today one has choice in 12V types with rpm controlled compressors.
Best is to avoid having to need inverters (any conversion really) but 12 to 5V won't be the hardest thing to do for things like DACs etc. with low currents. Use adequate DC cabling and sturdy switches but optimal is to use semiconductor switching. As power is the product of voltage and current a low voltage means higher currents so thicker cabling. High power and 5V means absurd thick cabling, the same power and 12V means reasonably thick but acceptable cabling. In practice this means you will have to use a DC rail system with right DC fusing/DC breakers and more groups than usual to be able to use "normal" wiring like 4 mm2. It would be good to seek advice from a local electrician. Make sure you keep to local regulations, wire codes/colors and that the insurance company still covers your stuff.
A book can be written how to stack the batteries and use them safely and wisely. Which is never IN a home.
Best is to avoid having to need inverters (any conversion really) but 12 to 5V won't be the hardest thing to do for things like DACs etc. with low currents. Use adequate DC cabling and sturdy switches but optimal is to use semiconductor switching. As power is the product of voltage and current a low voltage means higher currents so thicker cabling. High power and 5V means absurd thick cabling, the same power and 12V means reasonably thick but acceptable cabling. In practice this means you will have to use a DC rail system with right DC fusing/DC breakers and more groups than usual to be able to use "normal" wiring like 4 mm2. It would be good to seek advice from a local electrician. Make sure you keep to local regulations, wire codes/colors and that the insurance company still covers your stuff.
A book can be written how to stack the batteries and use them safely and wisely. Which is never IN a home.
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The source voltage is also important to consider. If you're converting from solar, Iirc some panels are a nominal 12V, with about 19V unloaded and somewhere around 17V when producing peak power.
Converting that to 12V or 24V would be more efficient as a general rule than down to 5V because of the switching ratios. If you look into buck regulators (probably the simplest switch-mode type, with parts readily available from Mouser and others), the datasheets often have full design examples.
There are other things you could do, like running a DC supply from the household solar panels, bypassing all the step-up and DC-to-AC conversion in situations where it's not strictly necessary, especially for high power like heating.
In fact, I can hardly think of anything at all that really needs 240Vac in the home, apart from maybe a couple of power tools that happen to have induction motors. And even that's questionable. The whole 'AC' thing is just an artifact of the legacy distribution system, and happens to be very dangerous too.
Converting that to 12V or 24V would be more efficient as a general rule than down to 5V because of the switching ratios. If you look into buck regulators (probably the simplest switch-mode type, with parts readily available from Mouser and others), the datasheets often have full design examples.
There are other things you could do, like running a DC supply from the household solar panels, bypassing all the step-up and DC-to-AC conversion in situations where it's not strictly necessary, especially for high power like heating.
In fact, I can hardly think of anything at all that really needs 240Vac in the home, apart from maybe a couple of power tools that happen to have induction motors. And even that's questionable. The whole 'AC' thing is just an artifact of the legacy distribution system, and happens to be very dangerous too.
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You need a powerbank designed for this operation. Check out, as example, the Volt Polska Sinuspro-800E. It is a combination of a inverter board and a charger board with independent voltmeters, ammeters and on/off switches.
Immersion heater, electric cooker, electric shower, heaters, tumble dryer, kettle (quick boil) Some of these are upto 7kW which is 30A at 240V.
These days most electrical appliances which aren't heaters only need a 100W or less, and for them a lower voltage (and DC) makes sense (modern LED lighting for instance). For a building though its never really going to make sense to run two sets of electrical wiring everywhere, and there is the issue of wiring faults/damage allowing high voltage wiring to short to the low voltage wiring (immediate fire hazard).
For something like a van or a boat 12 or 24Vdc makes a lot of sense. 5V is too low for distribution due to the very thick wiring required, 24V or higher makes sense, and these days buck converters can be fitted in an outlet if you want USB 5V. Compare to power-over-ethernet which uses 48V for distribution.
I have a number of automatic lights with their own solar panels for the outbuildings and some driveway alarms with panels, so I understand the simplicity and attraction of self contained solutions.
If that's the plan, I don't think there is much to discuss/debate, you purchase or build the devices as individual items. Possibly the use of common batteries and or solar panels and controllers.
If you are talking about wiring things into a common grid for efficiencies, then that's something different. The RV and presumably the House Boat folk have been doing this for years, there are already a plethora of solutions - but the manufacturers are pretty proud of them (almost like the "pink tax"),
I lived in an RV trailer for a while for ... reasons. Since you have a houseboat, none of this is likely new, however just in case...
The thing I learned was that if you don't have shore power, planning is essential and adding components (other than a phone/transistor radio/RC toy or something) usually requires re-planning your usage/storage/generation scheme. If you have shore power available, you are buying generally more expensive components and then power losses in converting shore power down, so I wouldn't put much beyond a weather radio, contact phone/radio, lights, and maybe a water pump on the DC system. The standard back in ~2006 for refrigerators if required was propane/natural gas (although that's not climate friendly).
I am not an electrical anything, my layman's vote would be for some type of 6/12/24/48V scheme that (with the right balancing charger) would seem to be easier to just parallel/series wire from a bank of 12V batteries and a couple 6V ones (never looked into deep cycle 6V so might not be a thing)...
If that's the plan, I don't think there is much to discuss/debate, you purchase or build the devices as individual items. Possibly the use of common batteries and or solar panels and controllers.
If you are talking about wiring things into a common grid for efficiencies, then that's something different. The RV and presumably the House Boat folk have been doing this for years, there are already a plethora of solutions - but the manufacturers are pretty proud of them (almost like the "pink tax"),
I lived in an RV trailer for a while for ... reasons. Since you have a houseboat, none of this is likely new, however just in case...
The thing I learned was that if you don't have shore power, planning is essential and adding components (other than a phone/transistor radio/RC toy or something) usually requires re-planning your usage/storage/generation scheme. If you have shore power available, you are buying generally more expensive components and then power losses in converting shore power down, so I wouldn't put much beyond a weather radio, contact phone/radio, lights, and maybe a water pump on the DC system. The standard back in ~2006 for refrigerators if required was propane/natural gas (although that's not climate friendly).
I am not an electrical anything, my layman's vote would be for some type of 6/12/24/48V scheme that (with the right balancing charger) would seem to be easier to just parallel/series wire from a bank of 12V batteries and a couple 6V ones (never looked into deep cycle 6V so might not be a thing)...
You will need à lot of converters because of the many different cases there exits.
You will end to the need of some standard voltage, then why not 120 AC ( or 230 AC in UE ).
You will end to the need of some standard voltage, then why not 120 AC ( or 230 AC in UE ).
