From left to right: David DiQuinzio, Brittany, Shaun and Sam

STEM Interns Brittany and Sam: We are here today talking to David DiQuinzio, CTO (that stands for Chief Technology Officer!) of Annapolis Hybrid Marine, about the new Tesla Battery.
David: How are you doing?
Brittany: Great, we are learning a lot about electric propulsion working here this summer! So Mr. David, can you tell us about the new Tesla battery that came out?
David: Yes, the new Tesla battery has gained a lot of interest and it's great news for homeowners who either already have solar or are looking at installing it. It's also good news for the marine industry, but in an indirect way. In other words, it is not a product that has a direct drop-in use in the marine world.
Sam: So is there a certain reason as to to why it isn't suitable in the marine world?
David: At your home, you receive power from the utility company over three wires. Two of them, which we call the 'hots', supply the power, and the other one, the neutral, is how the electrons that you buy from the utility find their way back. It's designed for 240 volts and that is what you get when you connect a load of some kind to the two hots. Meanwhile, your receptacles and anything needing 120 volts would all be connected between one of the hots to the neutral. 
Brittany: So what you are saying is that Tesla had to make this battery for the residential volts of 120/240?
David: Exactly.

Sam: But then how would they make it compatible?
David: Tesla had to design it so the energy that is stored in the battery, in the form of DC, could be inverted to AC.
Brittany: Oh! I heard about this! To do that you would have to store the energy and be able to control it, but also have to have a voltage at about 50% higher than the peak of what the AC is.
Sam: But isn't the 120/240 volts not the peak of the sine wave? Wouldn't it have to be like 170?
David: Yes, that's correct, but you also have to keep in mind the positive and negative halves of the AC sine wave. So you end up needing 350 volts or more of DC to be able to create residential power with an inverter. 
Sam: That is a great point!
David: Yes, and now let's think about what that means when you consider a situation with boats. Our propulsion equipment never uses more than 96 volts, and for most boats, their lights and instruments are 12 volts. So you could covert the Tesla battery's voltage down to these levels, but this involves specialized and costly equipment. 
Brittany: Now I know it's not a good fit with marine electric propulsion equipment, but wouldn't you be able to use it on a large boat or yacht just for the 240 volt or 120 volt house loads; things like appliances, air conditioners and charging stations? 
David: Yes, you could, but you would have to talk to your insurance company to make sure that they are ok with this and it meets boating industry standards.
*Customer walks in*
David: Looks like we will have to finish this another time.

Watch for Part 2 next week.