5 ms·
This Sparks Nevada presentation suggested that the Tesla mega-packs would play a role in delivering 1 MW in charging capacity (4X the rates of the newest Tesla
by powerbroker 4y ago
This Sparks Nevada presentation suggested that the Tesla mega-packs would play a role in delivering 1 MW in charging capacity (4X the rates of the newest Tesla cars).
The older (Austin?) introductory presentation (2017-2018) of the semi spoke of ridiculously low 7¢/kWh electricity availability (which even in Texas is a ridiculously low rate). I can't help but think that when you tack-on the added expenses of:
1. Site acquisition and leasing;
2. Permitting;
3. Design;
4. Trenching and installation;
5. Charger manufacturer;
6. Ongoing maintenance;
7. Added feature of a giant battery to feed the semi batteries
I'm finding it hard to imagine:
a) that 7¢ was even realistic for grid power backing in 2018;
b) that the enumerated costs above;
will be cost-competitive with current diesel prices.
Lastly, if its 30 minutes at 1,000 kW to reach 70% state of charge, then the battery is 500 kWh < x < 714 kWh. I'm thinking my math must be wrong somewhere... But if this is the ballpark, then this is going to be one expensive battery.
- chris222 4y agoThe battery is even larger than that. They did a 500 mile drive and claimed a slightly less than 2kWh/mi average efficiency. The peak charging rate is around 1MW. 7 cents/kWh is still doable with a large commerical solar farm and megapacks. My residential rooftop solar at over $3.00/watt installed is generating power at around that price (based on 25 year system lifetime). A commercial solar+storage solution should be able to hit that price.
- chris222 4y agoIf we isolate the battery pack cost it is likely between $100,000 and $150,000. This comes from some data suggesting Tesla was purchasing cells around $140/kWh a year ago. Lets assume the rest of the truck costs the same (it won’t) and the Tesla Semi is $100,000 to $150,000 more expensive than another diesel Semi truck. Average semi trucks get 6.5 miles per gallon and diesel fuel is around $5.00 per gallon right now. This translates to 77 cents a mile in fuel. Tesla semi uses 2kWh per mile. We can assume a hefty 20 cents/kWh price for commercial off peak power which translates to 40 cents a mile. With a delta of 37 cents a mile the $100,000 to $150,000 expense is paid off in ~300,00 to ~400,000 miles. Semi trucks are built to last around 750,000 to 1 million miles and drive an average of ~50,000 miles a year. Thus the payback comes in around year 6 or 7 of a ~15 year lifespan.
- vardump 4y agoI think $70/kWh on the cell level is closer to truth than $140. Might even be less at this point. A pack will of course have additional costs.