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The context of this post is the 2021 Toyota Sienna, which is a mild hybrid minivan. This approach works the same from either inside or outside the minivan. This approach also applies to cars with several USB ports. You might need to refer to the original thread for background or context.
The Low Voltage (LV) bus concept, explained below, also applies to bikepacking and ultra endurance biking. Ultra endurance biking means riding as far and as fast as possible in one or more days. The prototypical route is the 400 mile Tour Divide leg from Grand Teton, WY to Steamboat Springs, CO on a Specialized Creo Evo. The Creo has a 120 mile range at 28mph.
The LV bus concept applied to ultra endurance means recharging a battery, while the bike is actually in motion. Some power banks have 110VAC inverters, which facilitates eBike charging. Some power banks have a 72Ah capacity. Some power banks have solar power charging. Some solar panels are soft and can be rolled. The Creo frictionlessly decouples from the motor, so unpowered pedalling is possible.
The Creo charger draws a few amps and takes 3.5 hours to charge the main and Extender batteries, or about ten Ah. The LV bus approach achieves my target eBike range of 500 to 1,000 miles. The Tesla Cybertruck range is 500 miles!
The Sienna hybrid electrical system has an inverter and converter to transform 200VDC battery power to 110VAC, 12VDC or USB (5VDC). The Sienna also has two 110VAC outlets at 1500W.
- Simplification Rule #11: Build a Home Environment from USB Devices to Meet 80% of Your Needs, Powered by a 72Ah Portable Power Bank
The context of this post is the 2021 Toyota Sienna, which is a mild hybrid minivan. This approach works the same from either inside or outside the minivan. This approach also applies to cars with several USB ports. You might need to refer to the original thread for background or context.
The Low Voltage (LV) bus concept, explained below, also applies to bikepacking and ultra endurance biking. Ultra endurance biking means riding as far and as fast as possible in one or more days. The prototypical route is the 400 mile Tour Divide leg from Grand Teton, WY to Steamboat Springs, CO on a Specialized Creo Evo. The Creo has a 120 mile range at 28mph.
The LV bus concept applied to ultra endurance means recharging a battery, while the bike is actually in motion. Some power banks have 110VAC inverters, which facilitates eBike charging. Some power banks have a 72Ah capacity. Some power banks have solar power charging. Some solar panels are soft and can be rolled. The Creo frictionlessly decouples from the motor, so unpowered pedalling is possible.
The Creo charger draws a few amps and takes 3.5 hours to charge the main and Extender batteries, or about ten Ah. The LV bus approach achieves my target eBike range of 500 to 1,000 miles. The Tesla Cybertruck range is 500 miles!
The Sienna hybrid electrical system has an inverter and converter to transform 200VDC battery power to 110VAC, 12VDC or USB (5VDC). The Sienna also has two 110VAC outlets at 1500W.
I am extremely impressed by 12V and USB products. This means the minivan is essentially wired like a poor man's RV, because all seven passengers have their own USB port.
Amazon.com : USB Gadgets
12 Volt Appliances for Camping: Amazon.com
USB is 5VDC, so it is supported by the High Voltage (HV) battery via the 12V bus. Some products even switch between 110VAC and USB for different power needs; 110VAC cooking and subsequent 5VDC USB warming. You can achieve the same by freezing with 110VAC power and subsequently maintaining coldness with 5VDC USB.
Thinking in terms of a collection of USB devices that are switched between the hard-wired HV battery or a portable power bank is crucial. I refer to this concept as a Low Voltage (LV) bus. A universal power supply! Better yet is when USB devices are battery powered, e.g., Bluetooth speakers.
High capacity Power banks charged by solar power are also available. Charge the power bank during daylight hours, while using the minivan to power devices. Power devices at night from the power bank to avoid carbon monoxide poisoning, should the HV battery drain.
72Ah means a 10A device will run for seven hours! How much more power is needed for camping?
The LV bus supplies enough power to satisfy the following daily camping needs:
- My goal is to limit consumption to a few amps per hour, if any.
- Just multiply by 5V to estimate watts.
- Focusing on amps, to isolate power hungry devices.
- 5V is approximately battery voltage.
- Establishing an energy budget is essential to enjoyable experiences.
- Solar power might allow me to balance my energy budget, under certain circumstances.
The Low Voltage (LV) bus strengthens the case for mild hybrids, rather than PHEVs, for my specific purposes. In fact, i have eliminated PHEVs from consideration. The demand for HV battery capacity has been substantially reduced. In fact, some power banks provide 110VAC output. That means eBike batteries can be recharged from a power bank. I will look for the highest output wattage, which seems to be around 300W.
- Heat
- USB Sleeping bag or shawl.
- Light
- My USB bike light is probably more than adequate. I just need a lampshade.
- Ventilation
- Desktop fans drawing fresh air into the minivan through car ducts and exhausting air through moonroof.
- Electronics
- Laptops, cellphones, etc...
- Food Warming and Cooling
- Sound
- Bluetooth music players and speakers
The Low Voltage Bus approach brings relief, because the general solution is simplified to the point that i can track the major details and perform calculations in my head. I can temporarily ignore the High Voltage (110VAC) bus by separating it from LV bus concerns.
- I do not expect more than eight devices to run simultaneously.
- I do not expect average device voltage above 5V.
- Therefore, my main concerns when buying USB devices are:
- amperage
- battery capacity
- recharge rate
- I want to keep LV bus consumption below 10 to 12 amps, or 50 to 60 watts per hour.
- Recharging schedules can now be estimated.
- Eventually, all LV and HV details must be combined into a spreadsheet. i am far away from the optimization stage. I am at a preliminary approximation stage about general concepts of form and function.
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