DC Fast Charger Consumption Equivalent

A Kwh is a Kwh whether the load is a golf cart charger or a grocery store. I don't know who to ask about the L.A. grid specifics. Your questions are too vague to answer with any accuracy. Try again.

L.A. was just an example. I am trying to get my head around how big of a draw on a grid is 100 kwh a day. Would it be accurate to say that it's an equivalent of building 3.2 houses, if an ave house draws 920 kwh/month?

What's the average monthly need of a small grocery store?

This arithmetic is correct for the given assumptions, but 100 kwh/day represents only 2 hours/day of a 50-kw load.

For another comparison, 50 kw is equivalent to about 67 hp.

True, I doubt the charger will be used more than twice a day.

problem is that it does require high power wiring and load consideration on the power line and such high load changes sure make adverse effect on average power distribution systems. A use is only X2 hours but to be computed X24 hour bases for fixing load condition for the electricity supplier. Perhaps a generator is more suitable for such purposes.

Is 50kw considered to be a large load in a commercial setting? I understand that it would be in a residential area, but in a shopping strip it shouldn't be a problem

No not really. Many grocery stores and other retail places have base loads many times higher than that.

Larger places like shopping malls and other large business centers often run well into the megawatt power levels.

Industrial and manufacturing business can go well past that level so a 50KW load in the grand scheme of electrical service is not much, not even an average neighborhood on an average day.

A restaurant is apt to have 480V 200 A service if stoves are gas, and 480V 400A service if stoves are electric. (480 x 400 = 192kW) Most stores use less energy than restaurants -- some far less.

2000 square feet is about the size of a largish Starbucks, I'd estimate. Starbucks uses 5.84 kilowatt hours per square foot per year, so a 2000 foot store would use 11,680 kWh per year, or about 1000 kWh per month -- about the same as a typical house. A house will have 100A or 200A 220 v service, so if we assume 150 A as an average, then 33 kW is the (theoretical) peak house load.

"Is 50kw considered to be a large load in a commercial setting?"

Sure it is. We have 2kW normal load and then we have to tell the electricity distributor if we install extra load. They charge for extra load. Limit is the local distribution system like the transformer which deliverers power in local zone. Power is evenly distributed on three phase as well as load in time 24 hours.

Imagine there are 1000 houses for which we have 2kW per house allocated load, total 2MW average power. Now just 20 people bought this charger of 50kW for their cars and it add up 1MW extra load. If distribution system can not take 3MW then a new transformer is to be installed else power trip will be very often.

Engineering is by design and for a purpose.

Would it be accurate to say that it's an equivalent of building 3.2 houses, if an ave house draws 920 kwh/month?

I assume you mean is the additional load imposed about that of the load imposed by an additional 3.2 houses. Yes, assuming your usage assumptions are correct.

What's the average monthly need of a small grocery store?

It depends upon how small. Open refrigeration cases are not very efficient, especially when the store is being heated in the cold months. If the store has a bakery, the usage goes up from oven usage, but one could guess that a smallish store (whatever that might be) is probably equivalent to about 5 average houses.

The short answer to all this is that electric car usage, as it very slowly increases, will not cause infrastructure difficulties. The increases in the use of air conditioning in homes that has happened in the US since the 1960's has caused a large increase in electrical usage, in a way that is similar to the increase of usage that will occur as more electric cars are purchased.

Overall energy usage is predicted to continue to increase. However, if for a moment we assumed that overall energy usage were constant and the resources use for cars shifts from petroleum to coal and natural gas (via the grid) then the overall efficiency of transportation will improve a little, and in most areas of the country (but not all) the carbon footprint of cars would decrease slightly. (In areas where coal is used for almost all electrical energy production, then the carbon footprint of an electric car is a little high than that for an gasoline-powered one.)

Most people will not routinely charge with the high amperage charge stations, but will instead charge up overnight, at home, because it should be cheaper -- because night time rates are lower, and because there are no costs for the charge station installation, maintenance, real estate, profit for "convenience" etc. At the predicted growth rate of electric cars on the road, the existing infrastructure is adequate, because people typically charge their cars at night, when there is excess capacity.

Electric cars have the potential to aid in load levelling, by storing energy generated at night and selling it back to the power company during the daytime (while parked at work, and plugged-in for this purpose). The power company would have to pay me a pretty good incentive to do this, because the additional cycles on my batteries will cause me to replace batteries sooner than if I did not cycle them so deeply. Battery replacement is the largest cost associated with operating an electric car, and is on the order of $0.10 per mile. (Electricity costs are about 2.5 cents per mile in locations where electricity is 10 cents per kilowatt hour.)

80 x 50 Kw = 4 megawatts. thats not much really when comparing it to a city the size of LA. Many commercial and industrial manufacturing facilities use many times more than that by themselves.

100 KWh a day is not much either. I use around 1000 KWh a month just for my home and I live by myself. Anyone with all electric heat and appliances can easily use 5 - 10 times that around here.

For what its worth the United States as a whole uses around 4 Quadrillion watt hours a year. Thats 4,000,000,000,000,000 watt hours or about 1/5 of the worlds electrical power generation of around 20 quadrillion watt hours.

I gather you've been listening to the oil and coal lobby scare tactics. Note that you're using DC to charge the cars. Just charge a capacitor bank slowly and discharge it quickly. Or use lead acid batteries, which can also be discharged quickly and charged slowly. For purposes of comparison, a serious truck battery is about 2kwh. A serious electric car has about a 24 kwh battery. So properly arranged, a bank of say, 20 batteries would handle the transfer, at 240 volts and 200 amps for an hour. Charge the battery bank at a fifth that rate. Rinse and repeat. You're welcome.

And you are reading too many green sites plus apparently have no idea of cost.

I don't know why you say 'you're welcome' for such advice?

I would love to see a capacitor system that can store 24+ KWH and the price it costs!

Also using 20 deep cycle battery's to recharge another set of batteries of equal capacity will quickly wear them out which makes the battery to battery method a total waste of time and money to have. to work the primary storage battery bank would likely need to be around 10 -20 times the size of th vehicle batteries size in order to get any realistic service life out of it.

Perhaps reading up on capacitors and how they stack up to handle massive amounts of power and the relative cost of such a system and reading up on how batteries work and what and how things affect their service life would be a good idea.

When calculating multiple loads,such as apartments,multi family dwelling, etc, the NEC uses coincidence tables, which are de rating factors, because everyone is not going to be using everything at the same time.As the number of apartments go up, the total demand (per unit) calculation goes down.

So to answer your question, the actual number of chargers in use at any instant will have to be known, and the grid system has to be designed to handle the MAXIMUM peak demand of the systems.A typical home requires about 10KWH/day.

Ironically, the maximum instantaneous current draw in a home is a high wattage halogen lamp or an incandescent lamp.

What about an electric oven, heater, hot water service, toaster, micro wave or even the kettle you boil while you consider your reply. 2000 watts is quite common for a kettle. How many 2000 watt globes are there in a house?!

I appreciate that a bulb draws high current for a split second, but it is only a split second and many other element devices would exceed that.

Please bear into your GREEN equation the amount of energy to rewire the store, the trucks and fossil fuel to power the contractor's trucks, additional copper wire to be smelted, pulled and coated, steel conduit to be made and shipped, increased lithium or lead needed for batteries, plastic for the battery jars, pylons for chargers dug into the parking lot, yada-yada-yada. Not to mention the reams of paper for city, state and federal safety regulations, planning and approvals. The idea itself is not hopeless. One should keep in mind that the ancillary elements needed for satisfaction of an economical idea, may in fact, out weigh the ecological payback or an ecological return on rational - EROR.