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Tesla's Household Battery: Costs, Prices, and Tradeoffs
Technologist Ramez Naam (hat tip to Tyler Cowen's "Marginal Revolution" blog) has taken a look at the economics of Tesla's new wall-mounted household battery system, and concludes that it's "almost there," at least for many places in the world -- and seems to already make sense in some. From his analysis: For some parts of the US with time-of-use plans, this battery is right on the edge of being profitable. From a solar storage perspective, for most of the US, where Net Metering exists, this battery isn’t quite cheap enough. But it’s in the right ballpark. And that means a lot. Net Metering plans in the US are filling up. California’s may be full by the end of 2016 or 2017, modulo additional legal changes. That would severely impact the economics of solar. But the Tesla battery hedges against that. In the absence of Net Metering, in an expensive electricity state with lots of sun, the battery would allow solar owners to save power for the evening or night-time hours in a cost effective way. And with another factor of 2 price reduction, it would be a slam dunk economically for solar storage anywhere Net Metering was full, where rates were pushed down excessively, or where such laws didn’t exist.
That is also a policy tool in debates with utilities. If they see Net Metering reductions as a tool to slow rooftop solar, they’ll be forced to confront the fact that solar owners with cheap batteries are less dependent on Net Metering. ... And the cost of batteries is plunging fast. Tesla will get that 2x price reduction within 3-5 years, if not faster.
Golf cart batteries?! Umm no. Forklift maybe, dedicated Trojan or Rolls Royce batteries perhaps. I'd bet most solar installs in the US aren't off grid and are grid-tied. Pretty sure the grid-tie inverters won't automatically be setup to correctly charge a battery bank either and since these are lithium I'll also bet that most inverters that CAN charge batteries are setup for lead acid and not these. Yeesh...
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Net metering is when you have an energy producer (solar, wind, fuel cell, etc) that can at times produce more power than your house demand. The meter could flow backwards, meaning you are credited for the energy you produce. Some states don't have that, where the meter only spins one way, forward, so any back fed energy is blocked or has to be dumped to a battery or resistive load.
Time of use means you are charged different rates for electricity at different times of the day, as a function of wholesale price fluctuations. This is good and bad, since you lose price security but you can get the most benefit out of conservation.
Mixing the two lets you use a battery to arbitrage the price of energy, where you charge a battery at low prices and discharge at high price times. This works best with wind generation that tends to overproduce at night.
"the more batteries installed, the fewer people paying for electrical mains infrastructure"
non sequitur. You still need to load the bateries. Doing it without support from your mains is a big if.
As of 2015, the total levelized cost of coal is in the ballpark of solar/wind. (Levelized cost includes capital costs, but does not include pollution costs -- consider how cheap coal is that we count the cost of medical bills, let alone AGW.) In a few decades, it will be cheaper to use renewables than mine coal to run an existing coal plant. Notice how fast Kodak went out of business? That is what the coal industry is staring down.
Like all pain, suffering is a signal that something isn't right
Now the maximum temperature for the majority of Australian households in summer rarely if ever reaches or exceeds that. There is a large amount of the continent where the temperature exceeds that - however its very sparsely populated (you are looking at the central deserts after all) and has minimal infrastructure anyway.
For the majority of the population (i.e. major population centres on the coast) it's quite reasonable.
This guy copy-pasted his entire review from Gizmodo.
He's a plaigerist, not a technologist.
he's listed as the author on Gizmodo...
It's not an idiotic waste of energy if:
1) The energy would otherwise come from other, equally high grade (or even higher grade) energy sources, e.g. natural gas
2) The energy would otherwise come from non-renewable sources, e.g. natural gas
3) The energy would otherwise not be used at all due to overproduction
The monetary value of electricity flowing back into the grid on net metering is extremely low - much lower than the cost to purchase that electricity from the grid. If you have a choice between selling the power to the grid or using it to "generate low grade heat" with an electric stove, then the stove wins just on financial grounds.
If your argument is that you could use direct solar thermal methods to generate that heat - skipping the conversion to electricity - then sure it would be more efficient that way. When the source of energy is free, however, and you have already invested in the infrastructure for other reasons, it makes perfect sense to utilize solar electricity for cooking and cleaning. The alternative is to invest even more on additional infrastructure to utilize the same free energy source in a moderately more efficient way.
Use it or lose it, as they say.
=Smidge=
Solar city has a variety of financial plans available. I believe you are referring to the "SolarPPA" option, but leasing panels is also an option.
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".