Comments on: Tesla, SolarCity quietly selling building battery projects

By: keppelk

keppelk — Fri, 08 Jun 2012 04:38:42 +0000

Seriously? I think you mean deep cycle, rather than deep cell. And limetime on Lithium chemistry batteries is far better than any Pb based in the vast majority of conditions (charge/discharge rate, low SOC etc). Best lose the Czar and just be Mr Energy

By: ishekhar

ishekhar — Mon, 30 Apr 2012 18:29:59 +0000

$689/kwh looks like a more realistic number, considering the fact that in Ford Focus Electric a 23kwh battery pack costs the company anywhere from 14K to 16K.

By: Cam Coleman

Cam Coleman — Tue, 24 Apr 2012 18:43:25 +0000

The “lockout” you are refering to is specified in UL 1741. There are several manufacturers that have grid interactive inverters that have battery capabilities and are UL 1741 compliant. Outback and SMA are two manufacturers with such inverters. Often times when dealing with a utility you need to request what the specific points of concern are, then let the manufacturer respond to the concerns of the utility. This will allow the concerns of the utility to be voiced and addressed by the manufacturer who is very knowledgeable (and will speak the same language as the utility engineer).

By: mds

mds — Mon, 23 Apr 2012 04:07:16 +0000

What is the cost/kWh? What is the deep cycle life?

By: RobS

RobS — Sun, 22 Apr 2012 05:38:06 +0000

Because the big limitation of distributed renewables is their intermittent output, whilst their output can vary unpredictably through the day there ability to seriously penetrate grid supply is significantly limited. The one technology that can allow us to break free from a ~20% cap on intermittent renewable penetration is energy storage. This perception of the unreliable nature of renewable power is a major public relations issue for renewables which is commonly exploited to oppose support for renewable deployment. So this doesn’t do much for individuals at this stage except providing backup during power failures, but we need to develop it so that into the future renewables can grow beyond 20-30% without causing grid instability, and in the meantime to rebut criticism of renewables on the basis of unreliability.

By: MrEnergyCzar

MrEnergyCzar — Sun, 22 Apr 2012 01:42:30 +0000

These are sealed batteries so you wouldn’t want them for your home because they won’t last as long as deep cell lead acid batteries….

By: Hunter

Hunter — Sun, 22 Apr 2012 01:28:08 +0000

But see this underlines the basic weirdness of having battery storage in a grid-attached environment. The batteries aren’t producing any energy; the solar installation is. You can already sell the excess to the grid, so what’s the battery for? Since you’re grid attached, you can just buy power back from the grid when the cells aren’t producing.

Not sure I see the benefit to the person buying this in a grid-attached situation. Off-grid of course it makes all kinds of sense.

By: Don Johnston Parkhurst

Don Johnston Parkhurst — Sat, 21 Apr 2012 15:59:07 +0000

Here is the chance to go “off grid.” The one problem with my 7/2 kW SolarCity system is, that if the “grid” goes down, so does my solar system. While this is a safety issue to prevent utility workers from being injured while working on the “grid”, I would like to see the “lock out” device to be between the “grid” and my meter instated of between my solar system and meter. This movement of the “lock out” device would allow the solar system to continue to power my home even if the “grid” is down.
In researching this, I was told by Edison that the only way to do this was to go totally off grid. As an engineer, I see this as an attempt by the utility to overly complicate the use of alternative power sources. But it’s their ball park……. The cost of batteries was the deciding factor in not to complete the “off grid” alternative.
Hopfully these batteries will be cost effective.

By: Derek Jensen

Derek Jensen — Thu, 19 Apr 2012 02:45:32 +0000

Are these new packs? It seems like Tesla would be finding a way to reuse older packs that are starting to come out of the first Roadsters. If you’re buying a 10kWh pack, it shouldn’t really matter if that’s a 2 foot cube of new cells or a 3 foot cube of old cells.

By: Albert Hartman

Albert Hartman — Wed, 18 Apr 2012 19:44:01 +0000

It’s a great idea. We’re seeing how the PV panel market is actually healthier on rooftops versus at utility scale. Makes sense that battery storage would be healthier in home market versus electric vehicles also. The theme I see coming out is that cleantech sold to end users one-by-one may be a more viable way to start than the big sell a huge power utility approaches that we’ve seen so far.