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Comment Re:Sell batteries as an end product (Score 1) 232

Some details and pictures from when the boat was at the Miami Boat Show:

We had a number of different battery configurations that we tested to try and find the right balance of capacity and weight.

To get the batteries to charge that fast, the sunpads on the deck unfolded to expose more solar panels, and some dual surface panels were used that had higher output. We also had the batteries in banks that we could selectively charge (or discharge) them based on the power available

The goal was to have enough solar and batteries on board to be able to live on it, and not have to have a generator. Battery capacity was initially based on runtime targets, but was ultimately reduced to match the electrical demands of the boat while in "house mode"

The "hey we can have a smaller engine and help out with electrical power to get on plane" stuff came later.

Fun memory: I got (had) to test the GFI system we made, it blew some pyrofuses that disconnected the batteries in case something went wrong. It was a little unnerving to touch 700VDC, I used successively smaller resistors to be safe, but in the end did touch the bare battery cable, then did it again while the motors were under full load, and again under full regen:)

Working on boats sucks enough as it is, having to wear full PPE (personal protective equipment) in Florida while in the bilge gets old pretty fast!


Comment Re:Sell batteries as an end product (Score 2) 232

I worked on a hybrid boat with over 18,000 Li-ion batteries in the bilge!

(You don't want it to sink!)

It had 2 X 100 HP electric motors between the 500 HP diesels and the pod drives. You could run them for an hour at max output (about 12 knots) with the battery capacity it had, and you could get a whole days worth of putting around if you took it easy.

It recharged with solar panels in under a week, so you could use it every weekend using only the sun.

Recharging on shorepower was problematic to say the least. While it may be a 20 amp outlet, few of them can actually deliver 20 amps!


Comment Re:Drowning in microbeads (Score 1) 247

this one supplier can make 80 tons a month of just this one kind.

might as well take a whole shipping container full every month and just throw it in the ocean.

Then you figure how many people make this crap.

Then there's the soap sized chunks! The above is smeared into the pores, not just rinsed away like lava soap, how much of that do we make!

Comment Re:Help me out here a little... (Score 1) 533

I think (correct me if I'm wrong here) that if you have one or two houses with solar it is much easier for that power to be consumed by someone that is being fed power from the same transformer as you are.

This would seem like a much more manageable situation than if everyone had solar in your neighborhood and it has to start stepping up through the transformers looking for somewhere else to go.

Now if every neighborhood starts pushing power through the grid and all of these systems designed to put 10,000 amps one way go to shuffling around a few hundred amps from neighborhood to neighborhood.

Even if everyone had a radio link to the power company giving instant feedback of their generation, it would still be hard to keep voltage constant as clouds keep turning thousands of individual sources up and down.

With less and less power coming from the actual power company, who will be in charge of the grid? Imagine when we meet the break even point and power companies can shut off most of the day, who or what are all those thousands of separate Chinese inverters going to sync to?

In my imagination, I see waves of frequency, voltage and current fluctuations rippling uncontrollably around from transformer to transformer. Whole pulsating neighborhoods throbbing and blinking as these devices struggle to interoperate. A battle-royalle of cheap buggy firmwares fighting it to see who has the real 60 HZ... long after the power company automatically disconnected them.

Oh the voltage went up a little, I'll be a good little inverter and match it...

Oh hey the voltage went up a little, I'll be a good little inverter and match it.

That phase is kinda weird, good thing I can reshape it a little when I match it.

Wow my output just dropped 16 volts, Guess we need more juice quick, better step it up a notch!

Comment Re:Reminds of of something at a past job (Score 1) 765

I wrote a few gateway (protocol conversion) applications in assembly, and they were full of fun names and labels.

cp BeenWaiting, aWhile
brge CallTheBitchAgain

cp BeenWaiting, FuckingForever
brge WeGotFucked
CallTheBitchAgain: // because XYZ can't write a scheduler that works
decr TXbyteCounter
jmp RequestPacket

WeGotFucked: // because losing the state of a connected peripheral when they're too busy is an acceptable practice to some
jmp BandAidRestart
jmp ConnectWithKey

Comment Re:You're doing it wrong. (Score 1) 166

It's incredibly precise, I used to test ECU software to 12,000 RPM. That's 200 Revolutions per Second, or 72,000 Degrees per Second.

At 33Mhz, you have about 458 clock cycles per degree, so if you have a 60 tooth crank sensor with 6 degrees per tooth, you have a real time position update you need to task switch to, synchronize with, and schedule events on coming every 2750 clock cycles. In between them, you have to read filter and diagnose all of the sensors so you can look up, interpolate, and calculate all of the fuel and spark info, convert it back to binary time counts, then load or reload all of the different hardware timers safely at the proper time so they don't skip or wrap around.

You have to have over 7200 events (start and end of: fuel, air, spark on a 6 cyl, low emissions 2 stroke) happen at the exact time every second or the engine will misfire.

Starting with the Motorola MPC555 there was also a TPU (Time Processing Unit) that had multiple "self-synchronizing" counters and timers you can daisy chain, that took care of most of the heavy lifting (besides scheduling it!!!)

The TPU, along with a PowerPC core or two now allows modern ECUs to calculate everything based on a Simulink model of the engine while all of this is going on.

The best things in life go on sale sooner or later.