Recent content by schueppert

You are missing something. The HD Wave is using a distributed multi-level stepped output to produce something much closer to a sine wave before filtering and smoothing. This increases efficiency and reduces the quantity of magnetics required since it is transferring most of the analog signal...

I think you are on to something. Tesla has been successful with its car, in no small part, because the battery is much bigger than the competition. Perhaps even bigger than most people need. And a high price hasn't seemed to matter too much. Maybe they should have taken the same approach...

Cool thoughts. Quite a bit of smarts needed for the inverter to determine when to store excess power in the batteries and when to export to the gird. As OP question illustrates, power management needs are likely to be varied and complex. Export algorithm may depend on some or all of: time of...

SolarEdge are using powerline communication for their "Storedge" product. It's certainly possible Tesla is using this for PW also. But my guess is they will probably use RS485 instead. Most inverters, including SE and Fronius, already have a port for this. And the benefit of avoiding an...

Not at all, I'm a fan. But the quotes you provided support what I said: his existing implementation is based on off-the-shelf charge controllers, he knows this is a problem, he is building his own BMS, this is not a trivial task.

The WH057 thread is probably the most awesome discussion on this board. What he has done in amazing. But I'm not convinced his battery is going to last 10 years. He has basically removed/disabled the sophisticated Tesla battery management system and replaced it with off the shelf charge...

There are significant technical issues with connecting batteries in parallel. It's certainly is not an architecture that scales to utility level. Tesla has confirmed PW contains a DC-DC converter and it is hard to see why if it is just a dumb 350V battery as you suggest. And technical details...

As I say, I think you will find it works in exactly the same way as the SolarEdge optimizers. The SE optimizers are connected in series and the output from the string is a constant 350V volts regardless of how many optimizers are in the string.

I don't think any of those three statements is true. The Powerwalls work very much like the SolarEdge optimizers: they connect in series, but the total voltage of the string is constant. And so it's perfectly possible to control the voltage and power delivered by each unit. My interpretation...

I have my eye on something very similar: 3 kW PV /10 kWhr PW mostly as a grid backup system. I also received the same confirmation email but no call from SC; I don't even think they operate in my area. Any more details from your SC contact on system design/performance/cost?

Sure, they state 10 year life. But that's at 1,000,000 cycles. They don't provide any data on the relationship between cycles and life years, but it seems reasonable to assume that if you only cycle it once a day then the life would be a lot longer and the capacity reduction much smaller.

As I said, the problem is an 85 kWh super capacitor pack using current technology would be bigger and heavier than a lithium battery pack. You might imagine super capacitors would benefit from the same miniaturization as other solid state electronics, but that really isn't the case. As you...

This is great. Let's hope MB and Tesla cooperate so their batteries are compatible (supported by the same inverters etc.). In particular I would like to see MB support high voltage DC (350V DC) to help establish this as a standard. There's plenty of opportunity for both MB and Tesla if they...

Actually you use a variable frequency drive. Super capacitors operate at a voltage of about 3v. So you can imagine assembling many of these in series/parallel to form a pack operating at say 600V rather like the Tesla pack works today with lithium cells. You then connect the output of the...

Umm...Ohm's Law.