They have solar + batteries, so they have to convert the sun into DC, hopefully directly supply that DC to their batteries, then convert that DC to AC power, then convert that AC power back to DC. Converting AC to DC or vise versa is a reasonably lossy process, so not doing double the conversion is even better.
Also some less than ideal setups convert solar directly to AC, so in order to charge your batteries you have to convert it back to DC.
Thanks, glad to have inspired you! The other person who replied is spot on. I have an entirely DC system so my main advantage comes from cutting out pointless double-conversion from dc to ac back to dc again. Powering on an DC to AC inverter is a parasitic draw that consumes enough power to eat through a good amount of battery capacity if left on by itself. Then using that AC inverter just to power another inverter to step back to DC introduces even more losses and parasitic load. So, its worth my time to try figuring out ways to directly power devices by directly converting DC to DC voltages and cut those needless loads out greatly boosting total efficiency.
USBC-PD technology is an incredibly useful innovation for direct variable dc to dc voltage supply. Specifically a 100 watt usbc-pd charger can supply 5v,9v, 15v, 20v at up to 5 amps (5Ax20V=100 watts). A car cigarette plug can supply 12V at 10A or 120 watts of power. Together they can directly power a great many household DC appliances off of batteries powering a DC to DC inverter.
For some examples:
A 24" lcd computer monitor at full brightness consumed 50Wh through AC inverter. It was brought down to 25Wh running through DC inverter. On half brightness it consumed 15Wh and 10Wh at minimum brightness.
A thinkpad laptop full brightness was 25wh idle -50wh full load, then brought down to 12-20wh.
My nintendo switch game console docked into the lcd screen consumed about 15-20Wh with inverter, brought down to 10Wh.
Desktop dry herb vaporizer (Arizer Extreme Q): 80Wh heating up, 30-50wh idle brought down to 50Wh heating up 15-25Wh idle.
Electric blankets. During the cold months using my electical energy to help keep warm is very important to me. But I cannot keep a regular house electric blanket on for more than an hour or two. I could not keep a car plug blanket on overnight at 80wh. I could keep on a USB powered blanket on overnight at 10-15Wh. And you know what suprised me most? It was damn warm, when I figured out the right way to sleep with it. Have to sleep on it as a matress warmer and layer some heavy blankets on top and let it warm up for an hour or two. But it works and works well. The USB blanket doubles as wearable poncho too which is nice. I wish a USBC-PD one existed with variable wattages.
So as you can see each time I macguyver a way to directly power these devices the total power usage is cut by almost half per device. To someone else who can afford an array of solar panels and a massive bank of batteries they can get away with not caring about saving 20Wh here or 15Wh there. I have a very modest system of 200watts solar feeding into ~400Wh battery capacity total so these savings mean the difference between my batteries being dead overnight and having lots of spare juice left over to brew a cup of coffee with those AC inverters when I wake up.
Of all these devices listed, the LCD monitor is one that has a noticable parasitic load even when the screen is off it consumes a noticable amount of power at idle. The way I would deal with most instances of parasitic draw like this is to find a product throws a physical switch to manually cut contacts with the DC-DC inverter when not being used. In this case a car plug extention cable with a knife switch built in would work great.
Okay so the magic sauce here is USBC-PD which is some type DC-DC voltage converter. Then it’s just a matter of barrel connector roulette to find the appropriate plug for each device.
I live part time out of an RV semi-off grid for some of the year and the “using AC/DC power packs off an inverter” always struck me as super dumb which your data basically confirms.
What you’ve given me is a roadmap to figure this out without having to reinvent the wheel.
You got it man, right on. I would like to give you some more information about the usbc-pd stuff and some of the things I figured out with it. So here is a link to the farsense usbc-pd to standard DC 5.5x2.5 adapter with manually selectable voltage based on button press. This cable is the most important part and I will explain why its so important. USBC-PD essentially requires three things to work right.
The first thing is a charger(the DC to DC inverter in our context) ideally rated at either 65w or 100w as both of those support up to 20v the difference being 65W can only go up to like 3.25 amps or something like that. The simplest and cheapest dc to dc chargers are usbc-pd car plug chargers which convert the 12v from a car battery to the required voltages. The anker one I just linked is a little pricy you can find them for cheaper but it seems good quality and I like the cable I bought from them.
Speaking of, the second thing you need is a USBC-PD power cable that specifically supports the same wattage your charger outputs. Not all of them are rated the same you gotta use a specifically rated cable that handles higher voltages. If you use a 100W charger gotta get a 100W cable. I’ve had good luck with this anker one
The third and most crucial thing to understand for our purposes, is that you need a communication chip on the appliance side that tells the charger/inverter what voltage to send. The nice thing about that farsense manual voltage selector cable is that it has that communication chip built in with all the different voltages to pick from. Thats the real secret sauce of this setup. That cable and its ability to choose voltage levels is the heart of it. All thats left is to track down the specific dc 5.5x2.5 to X adapter bit and select the proper voltage on the cable and its good to go.
There are USBC-PD adapter bits that have this chip built in for a specific voltage, commonly for laptops at 19-20v. If you manage to track down the proper usbc-pd to barrel plug adapter at your specific needed voltage it will cut out having to manually set the voltage each time you plug it in compared to the farsense cable. But it may be hard tracking down such a specific adapter bit.
You have inspired me.
Are you suggesting that modern USBC power supplies don’t have that parasitic draw that other DC power packs have?
They have solar + batteries, so they have to convert the sun into DC, hopefully directly supply that DC to their batteries, then convert that DC to AC power, then convert that AC power back to DC. Converting AC to DC or vise versa is a reasonably lossy process, so not doing double the conversion is even better.
Also some less than ideal setups convert solar directly to AC, so in order to charge your batteries you have to convert it back to DC.
Thanks, glad to have inspired you! The other person who replied is spot on. I have an entirely DC system so my main advantage comes from cutting out pointless double-conversion from dc to ac back to dc again. Powering on an DC to AC inverter is a parasitic draw that consumes enough power to eat through a good amount of battery capacity if left on by itself. Then using that AC inverter just to power another inverter to step back to DC introduces even more losses and parasitic load. So, its worth my time to try figuring out ways to directly power devices by directly converting DC to DC voltages and cut those needless loads out greatly boosting total efficiency.
USBC-PD technology is an incredibly useful innovation for direct variable dc to dc voltage supply. Specifically a 100 watt usbc-pd charger can supply 5v,9v, 15v, 20v at up to 5 amps (5Ax20V=100 watts). A car cigarette plug can supply 12V at 10A or 120 watts of power. Together they can directly power a great many household DC appliances off of batteries powering a DC to DC inverter.
For some examples:
A 24" lcd computer monitor at full brightness consumed 50Wh through AC inverter. It was brought down to 25Wh running through DC inverter. On half brightness it consumed 15Wh and 10Wh at minimum brightness.
A thinkpad laptop full brightness was 25wh idle -50wh full load, then brought down to 12-20wh.
My nintendo switch game console docked into the lcd screen consumed about 15-20Wh with inverter, brought down to 10Wh.
Desktop dry herb vaporizer (Arizer Extreme Q): 80Wh heating up, 30-50wh idle brought down to 50Wh heating up 15-25Wh idle.
Electric blankets. During the cold months using my electical energy to help keep warm is very important to me. But I cannot keep a regular house electric blanket on for more than an hour or two. I could not keep a car plug blanket on overnight at 80wh. I could keep on a USB powered blanket on overnight at 10-15Wh. And you know what suprised me most? It was damn warm, when I figured out the right way to sleep with it. Have to sleep on it as a matress warmer and layer some heavy blankets on top and let it warm up for an hour or two. But it works and works well. The USB blanket doubles as wearable poncho too which is nice. I wish a USBC-PD one existed with variable wattages.
So as you can see each time I macguyver a way to directly power these devices the total power usage is cut by almost half per device. To someone else who can afford an array of solar panels and a massive bank of batteries they can get away with not caring about saving 20Wh here or 15Wh there. I have a very modest system of 200watts solar feeding into ~400Wh battery capacity total so these savings mean the difference between my batteries being dead overnight and having lots of spare juice left over to brew a cup of coffee with those AC inverters when I wake up.
Of all these devices listed, the LCD monitor is one that has a noticable parasitic load even when the screen is off it consumes a noticable amount of power at idle. The way I would deal with most instances of parasitic draw like this is to find a product throws a physical switch to manually cut contacts with the DC-DC inverter when not being used. In this case a car plug extention cable with a knife switch built in would work great.
Okay so the magic sauce here is USBC-PD which is some type DC-DC voltage converter. Then it’s just a matter of barrel connector roulette to find the appropriate plug for each device.
I live part time out of an RV semi-off grid for some of the year and the “using AC/DC power packs off an inverter” always struck me as super dumb which your data basically confirms.
What you’ve given me is a roadmap to figure this out without having to reinvent the wheel.
You got it man, right on. I would like to give you some more information about the usbc-pd stuff and some of the things I figured out with it. So here is a link to the farsense usbc-pd to standard DC 5.5x2.5 adapter with manually selectable voltage based on button press. This cable is the most important part and I will explain why its so important. USBC-PD essentially requires three things to work right.
The first thing is a charger(the DC to DC inverter in our context) ideally rated at either 65w or 100w as both of those support up to 20v the difference being 65W can only go up to like 3.25 amps or something like that. The simplest and cheapest dc to dc chargers are usbc-pd car plug chargers which convert the 12v from a car battery to the required voltages. The anker one I just linked is a little pricy you can find them for cheaper but it seems good quality and I like the cable I bought from them.
Speaking of, the second thing you need is a USBC-PD power cable that specifically supports the same wattage your charger outputs. Not all of them are rated the same you gotta use a specifically rated cable that handles higher voltages. If you use a 100W charger gotta get a 100W cable. I’ve had good luck with this anker one
The third and most crucial thing to understand for our purposes, is that you need a communication chip on the appliance side that tells the charger/inverter what voltage to send. The nice thing about that farsense manual voltage selector cable is that it has that communication chip built in with all the different voltages to pick from. Thats the real secret sauce of this setup. That cable and its ability to choose voltage levels is the heart of it. All thats left is to track down the specific dc 5.5x2.5 to X adapter bit and select the proper voltage on the cable and its good to go.
There are USBC-PD adapter bits that have this chip built in for a specific voltage, commonly for laptops at 19-20v. If you manage to track down the proper usbc-pd to barrel plug adapter at your specific needed voltage it will cut out having to manually set the voltage each time you plug it in compared to the farsense cable. But it may be hard tracking down such a specific adapter bit.