User avatar
Marktm
Gold Member
Posts: 655
Joined: Thu Jan 21, 2016 10:49 am
Delivery Date: 09 Jan 2016
Leaf Number: 022737
Location: Houston, TX

Re: Texas, ERCOT, PUC and the severe winter storm

Fri Apr 02, 2021 6:14 am

ripple4 wrote:
Tue Mar 30, 2021 5:40 am

Here is weather station data from Houston and it has good sun for 3 out of the 4 days. In my experience a few hours over 300w/m2 will put a meaningful amount of power in an off-grid battery. Texas had 4 hours of good sun on the 15th and 16th, the 17th was bad, and then the 18th was about 2 hours worth. A Tesla solar + powerwall customer or solar off-grider would have been well taken care of.

I used my actual usages during those four days and the actual average daily cost per kWH (3 days were $9/kWH). I then integrated the days solar wattages from the weather data (grosso-modo for sure!) and made some assumptions about efficiencies. A sweet spot for me would be a 9-10kW array with a V2X enabled Leaf plus - that would be sitting in the garage anyway - as roads were impassable. If we had lost power, then we would have had enough battery energy to keep the gas furnace and fridges going the entire time and saved around $800 of charges for the entire event. Since we did not ever lose power, and we were not at home the entire time, the result would have been making a little money by selling back overall and saving over $650 in energy costs for the 4 days. This would require the proper "smarts" for energy management and/or internet based controls with a small UPS backup for the router.
2012 Leaf SL
2021 Leaf SV Plus

ripple4
Posts: 98
Joined: Tue Sep 18, 2018 1:45 pm
Delivery Date: 18 Sep 2018
Location: Toledo, Ohio

Re: Texas, ERCOT, PUC and the severe winter storm

Fri Apr 02, 2021 8:45 am

I'm not sure vehicle to grid is ever going to take off. The industry has had lots of time to think about it and make a business case, and nobody's done it commercially in the USA. I think the reason is that electricity in a vehicle battery is much more valuable than it may seem, its priced in gasolines' value, where home power is priced at a much lower cost. Maybe, from the end users perspective, home batteries are cheaper than EV batteries.

you talk about the smart home brain, this video shows how one guy did it, only selling back at the highest price. he must have had a power plan that is like the griddy plan, with the unfiltered wholesale price available to him. with all that custom development, i doubt it will ever pay off, but he is on TV so maybe that's what he wanted. if that approach was in widespread used, where home batteries were dispatchable, that would be a good outcome. Taken as a whole they call that a virtual power plant, but these are not grass roots things, they are top-down at this point.

https://youtu.be/yxABosWfuus?t=724

I'm not a fan of the pajamas media website that is linked here, they rebranded it 'PJmedia' now i see. on the wikipedia site, most of the space is used listing how they have been caught making false claims. https://en.wikipedia.org/wiki/PJ_Media

LeftieBiker
Moderator
Posts: 16911
Joined: Wed May 22, 2013 3:17 am
Delivery Date: 30 Apr 2018
Location: Upstate New York, US

Re: Texas, ERCOT, PUC and the severe winter storm

Fri Apr 02, 2021 1:03 pm

I think that V2Home will be a fairly small niche market, and that's about it. Give me a 5+kw unit for no more than $3k, and I'll buy one. I'm tired of dealing with generators, and it's now too hard for me, even with the gen now residing in an enclosure near the connection port.
Brilliant Silver 2021 Leaf SV40 W/ Pro Pilot & Protection
2009 Vectrix VX-1 W/18 Leaf modules, & 2 lithium E-bicycles.
BAFX OBDII Dongle
PLEASE don't PM me with Leaf questions. Just post in the topic that seems most appropriate.

Triggerhappy007
Posts: 142
Joined: Tue Jan 01, 2019 8:08 pm
Delivery Date: 01 Jan 2019

Re: Texas, ERCOT, PUC and the severe winter storm

Sat Apr 03, 2021 5:23 am

Marktm wrote:
Mon Mar 29, 2021 3:02 pm
Comments from my experience in Houston, TX using Griddy - a retail provider - during the Texas storm:
- My contract with Griddy is basically a subscription fee of $10/month - and pay whatever energy cost is set by ERCOT/TX PUC over 15 min interval (may be 5 min average - would have made little difference during this event).
- There were several days of continuous $9/kWH pricing (yes, 900 cent/kWH). Not being at home and having gas heating, my consumption was only 20-30 kWH per day. Even with this low usage, my electrical bill during this extreme event was over $1000 - anecdotally that some where over $10,000.
In the past, did you save money while you were on Griddy? What were your average cents per kWh including taxes and fees?

I heard a lot of advertising from them on the radio a few years back and even considered switching but I'm glad I didn't.
2020 Leaf Plus SV Tech & All Weather
2019 Leaf SL - traded in
2020 Pacifica Hybrid Limited AST

User avatar
Marktm
Gold Member
Posts: 655
Joined: Thu Jan 21, 2016 10:49 am
Delivery Date: 09 Jan 2016
Leaf Number: 022737
Location: Houston, TX

Re: Texas, ERCOT, PUC and the severe winter storm

Sat Apr 03, 2021 6:42 am

Triggerhappy007 wrote:
Sat Apr 03, 2021 5:23 am

In the past, did you save money while you were on Griddy? What were your average cents per kWh including taxes and fees?

I heard a lot of advertising from them on the radio a few years back and even considered switching but I'm glad I didn't.
Griddy used the average all in cost in the ERCOT domain and compared to my actual all inclusive cost and I had saved around $1200 over a 28 month period - very substantial as I'm not a huge user ($100/month average). I'd watch fairly often, especially during the summer and would text my wife to not use the oven/stove and turn up the A/C a couple of degrees when the fairly predicitable spikes occurred. So it took some work. I also precooled the house during the night and typically only charged my Leaf during early morning. It was actually a fun challange that if everyone had practiced, our ERCOT grid would be so much more stable!
2012 Leaf SL
2021 Leaf SV Plus

Triggerhappy007
Posts: 142
Joined: Tue Jan 01, 2019 8:08 pm
Delivery Date: 01 Jan 2019

Re: Texas, ERCOT, PUC and the severe winter storm

Sat Apr 03, 2021 7:40 am

Marktm wrote:
Sat Apr 03, 2021 6:42 am

Griddy used the average all in cost in the ERCOT domain and compared to my actual all inclusive cost and I had saved around $1200 over a 28 month period - very substantial as I'm not a huge user ($100/month average).
How many kWh do you use a month?
2020 Leaf Plus SV Tech & All Weather
2019 Leaf SL - traded in
2020 Pacifica Hybrid Limited AST

User avatar
Marktm
Gold Member
Posts: 655
Joined: Thu Jan 21, 2016 10:49 am
Delivery Date: 09 Jan 2016
Leaf Number: 022737
Location: Houston, TX

Re: Texas, ERCOT, PUC and the severe winter storm

Sat Apr 03, 2021 2:41 pm

My usage varies so much because of A/C:
Peak summer ~ 2000+ kWH - June thru Sept.
Mid fall/winter/spring - 600-800 kWH
All in rate for entire 28 months = 9 cents/kWH (before the ERCOT disaster - a one month bill of over $1000 with only 20 - 30 kWH/day)
2012 Leaf SL
2021 Leaf SV Plus

User avatar
Marktm
Gold Member
Posts: 655
Joined: Thu Jan 21, 2016 10:49 am
Delivery Date: 09 Jan 2016
Leaf Number: 022737
Location: Houston, TX

Re: Texas, ERCOT, PUC and the severe winter storm

Sat Apr 03, 2021 3:11 pm

For those interested in the Griddy bankruptcy (and some damn good reasons to pass blame to ERCOT):
https://www.griddy.com/

This should be a good test of our "two tiered" justice system - we'll see.
2012 Leaf SL
2021 Leaf SV Plus

Triggerhappy007
Posts: 142
Joined: Tue Jan 01, 2019 8:08 pm
Delivery Date: 01 Jan 2019

Re: Texas, ERCOT, PUC and the severe winter storm

Sat Apr 03, 2021 10:05 pm

Marktm wrote:
Sat Apr 03, 2021 2:41 pm
My usage varies so much because of A/C:
Peak summer ~ 2000+ kWH - June thru Sept.
Mid fall/winter/spring - 600-800 kWH
All in rate for entire 28 months = 9 cents/kWH (before the ERCOT disaster - a one month bill of over $1000 with only 20 - 30 kWH/day)
9 cents/kWh is a lot cheaper than what TXU or Reliant charges, but that's about what the lowest electric providers charge for a 12 month+ contract. Have you used the price comparison site, powertochoose.org?
2020 Leaf Plus SV Tech & All Weather
2019 Leaf SL - traded in
2020 Pacifica Hybrid Limited AST

User avatar
Marktm
Gold Member
Posts: 655
Joined: Thu Jan 21, 2016 10:49 am
Delivery Date: 09 Jan 2016
Leaf Number: 022737
Location: Houston, TX

Re: Texas, ERCOT, PUC and the severe winter storm

Sun Apr 04, 2021 6:38 am

I have not done a cost comparison of the "cheapest" - generally because these advertised costs don't work well for me as I'm a low consumer and there are usually fixed costs (and sometimes almost hidden) added on that make the "all-in" different than the advertised. That being said, the $10/month "subscription" fee AND the credit card fee (sort of hidden) made it difficult to achieve really low "all ins" during my low usage months. My main goal was to see how much influence I could make by regulating my main users - and I'm convinced that using V2X with a really cheap Leaf battery - and solar - would have a significant payback. Plus give me a "low carbon" resilient system that I could get real life experience with. I have two solar systems installed at a rural location and I'm quite familiar with the cost/benefits at a location that is powered by a co-op at a "fixed" rate. It is difficult in TX as energy rates are soooo low! However, overall US, a "smart" control system with a modest solar/battery storage system could make qute a difference in the grid stability/resilience - just IMHO.
2012 Leaf SL
2021 Leaf SV Plus

Return to “Solar”