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Tesla Energy

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Re: Tesla Energy

#141

Post by colinsidoti »

kmod wrote: post #91
colinsidoti wrote: post #51

One thing that might go overlooked: Load shifting could, in theory, lower electric bills such that there's ROI without solar panels. --- Edit for why: On-demand power is expensive. "Spinning up" additional power during the day is more expensive than having certain types of power generation running all the time. In theory, pumping power into a battery at night during non-peak hours will cost less than consuming direct…

If what you say is true, then with better economies of scale and longer investment horizons, utilities would quickly erase any peak-vs-non-peak arbitrage opportunities.

It's hard to wrap your head around all the challenges in energy. If you're REALLY good at it you can find some incredible arbitrage opportunities...see Enron.

Consider the power output characteristics of some common energy sources:

Gas, Nuclear, Hydro, Wind, Solar

Our "sustainable" sources of power - hydro, wind, and solar - are also the ones with the most irregular and unpredictable power output. This creates a problem, because even if there was enough cumulative power output from sustainable sources today, it most likely wouldn't align with our usage schedule.

So there are two solutions: 1) find a way to map the sustainable power output to our usage 2) find a way to store energy

Today, our most readily available form of energy storage is gas. We just put it in a container and burn it when we need to. "Spin it up," if you will.

An alternative to gas is a crazy network of Powerwalls. The hope is that, eventually, instead of spinning up gas turbines during peak demand, we can just draw from our Powerwall.

There was another alternative on HN recently. Basically a super-deep hole in the ground with super heavy object falling into it, but suspended by a rope. You run a motor to lift the object during off-peak hours, then let it fall and spin a generator during peak hours. I can't find it right now but I remember thinking they had a great name.

---

That said, power output is only part of the problem. If you're looking to factor the potential disappearance of arbitrage opportunities into your buying decision, you also need to consider the time until regulatory changes allow for perfect pricing, and the time until these Powerwalls have precise enough information to decide exactly when to draw from the grid versus the battery.

tl;dr: "quickly" is probably optimistic. We're a long ways away from economies of scale.

Re: Tesla Energy

#142

Post by bzbarsky »

reality_czech wrote: post #128
BinaryIdiot wrote: post #49

Earlier quoted context omitted.

> I expect from today onward there will be a full-scale attack from those who stand to lose because of the reduced dependency on oil. Maybe. But remember we don't have the technology yet to completely move away from fossil fuels. The biggest issue I know of is making Airplanes electric which so far has not proven really feasible (as far as I can find anyway). This solves a huge chunk of issues but there are still ple…

Zepplins can be run with very minimal environmental cost. They are slower, though. Airplanes are extremely energy-hungry and carbon-intensive. Just one intercontinental round trip can put as much carbon per person into the air as a half a year of driving, assuming you have a new-ish car. And yes, this is after dividing the total emissions by the number of passengers.

An intercontinental round trip is in the range of 10-15k miles, right? That's a plausible mileage for 6 months of driving, sure. Would match up with my understanding that fuel use for planes per passenger-mile is about the same as for cars with just a driver.

The big difference, of course, it that it takes a lot less time to travel that many miles in a plane. But on a per-passenger-mile basis they're no worse than non-carpooling cars. Admittedly a low bar.

Re: Tesla Energy

#143

Post by CamperBob2 »

Enough energy to power a single family home for 1.8 billion years or supply energy to a nuclear power plant for 2,300 years

I think I see the problem...

Re: Tesla Energy

#144

Post by bzbarsky »

josephagoss wrote: post #105
iandanforth wrote: post #39

I might spend $480 on electricity per year. I can't see this thing having an ROI within its lifespan. I also don't have solar panels, and have a very reliable power grid. Any reason I should consider buying one?

We spend over $2,000 per year and it's just me and my girlfriend. From the sounds of it you have either very good rates or perhaps a frugal lifestyle? Either way it's impressive.

We spend less than that for a family of 5.

But that's not impressive at all; all these numbers really depend on what that electricity is being used for. Our heat and hot water are not electric. AC doesn't get used much, since we're far enough north (Massachusetts) that it's not a big deal. So that leaves lights, electronics, and the stove/microwave/vacuum...

My parents, on the other hand, are in the DC area, electric AC, heat, hot water. They're spending probably triple what you are on electricity.

Anyway, point is counting just electricity spending is typically comparing apples and oranges. You want to include the natural gas or oil or whatever else people are using for heat if you want to get numbers that are even remotely comparable.

Re: Tesla Energy

#145

Post by curiousDog »

Do these green numbers take into consideration the energy expended on producing the Li-ion batteries? Surely that must be a messy mining operation.

Re: Tesla Energy

#146

Post by rodgerd »

kondro wrote: post #124
toomuchtodo wrote: post #90

Earlier quoted context omitted.

But they could now, and most deep cycle lead acid batteries are flooded, not sealed, which means they have to be ventilated to prevent hydrogen explosions hazards. Not so with Tesla's offering.

Fine. 4.8kW Li-Ion battery for USD$3,278 1.9kW for USD$1,678. My point is that Tesla isn't really doing anything really unique here. Sure, they're giving it more press than anyone really has before, but the products aren't especially cheap, innovative or special. http://ironedison.com/12-volt-lithium-battery-for-solar

Less storage than a Nomad.

Re: Tesla Energy

#147

Post by morekozhambu »

thewarrior wrote: post #134

Wow This thing could sell like crazy in places like India. 10 kwH is enough to power an Indian home for more than a day and at 3500 dollars most middle class people would consider buying it seeing how frequent power cuts here are.

10 kWh is good spec. But $3500 is around Rs. 2.1 lakhs. That's a way too costly UPS(inverters) considering a 1kWh one costs within Rs. 25k and bumping it two more car batteries.

Re: Tesla Energy

#148

Post by r00fus »

josephagoss wrote: post #105
iandanforth wrote: post #39

I might spend $480 on electricity per year. I can't see this thing having an ROI within its lifespan. I also don't have solar panels, and have a very reliable power grid. Any reason I should consider buying one?

We spend over $2,000 per year and it's just me and my girlfriend. From the sounds of it you have either very good rates or perhaps a frugal lifestyle? Either way it's impressive.

I think it depends on your house size and whether you have a pool, etc. When we lived in an apartment, we spent $40-50/mo on utilities total.

I have a family of 5 in a small home and we spend $1200/yr in pricey CA (rates start at 16c/kWh going up to 35c). We don't run AC (whole house fans/attic fans), and use room heaters in winter.

Re: Tesla Energy

#149

Post by seanp2k2 »

milesf wrote: post #33

Today is a big deal. Open sourcing the patents to build fully solar-powered electrical grids around the will be a paradigm shift in the power structures of the world. I expect from today onward there will be a full-scale attack from those who stand to lose because of the reduced dependency on oil. First they ignore you. Then they laugh at you. Then they fight you. Then you win.

Most of the power in the US comes from coal. Solar is 0.4%: http://www.eia.gov/tools/faqs/faq.cfm?id=427&t=3

What do you do with the batteries and the toxic materials inside when you're done with them (and how long do they last)?

What do you do with all the toxic materials produced during mining, refining, and production of batteries and materials?

How do you deal with these same issues as they affect solar panels, which are made of silicon?

Re: Tesla Energy

#150

Post by latch »

thewarrior wrote: post #134

Wow This thing could sell like crazy in places like India. 10 kwH is enough to power an Indian home for more than a day and at 3500 dollars most middle class people would consider buying it seeing how frequent power cuts here are.

Really? According to wiki, India's middle-class makes anywhere from $10 to $50 per day. When you factor in that this will cost a lot more than $3500, would these really sell like crazy?
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