What's so bad about selling to utility wholesale?

[thewilliam]

For some reason this thread got me thinking about small off grid  application specific additions to my grid tied system as an alternative to adding grid tied storage. Specifically a system to power a (or some) mini-splits to assist my 35+ year old undersized air conditioning during peak rates and declining production, 4-9 pm. Or a stand alone system for my pool equipment. If it's not too far OT I'd appreciate some comments on that - a blend of off grid and grid tied pv. Best of both worlds? Too many complications? I'm not looking to short change the utility but it does seem they need some help or a bit of relief till they figure out how to  fix their grid and have time to implement it. As long as there is a reasonable roi.

I have a new grid tied system and I don't think I would want my whole house to be off grid. I don't mind paying for grid infrastructure cost separate from electric use and appreciate the grid being my battery.

My system's size should cover almost all my annual usage but I was worried that the switch to tou rates would reduce my savings and increase the time for it to pay for itself (reduced roi) as my largest load (a/c) by far is peak summer rate during declining production. June had awesome overproduction which net metering banked for me. I guess I won't know the whole tally till July, August, September roll by.

 

[1201]

For some reason this thread got me thinking about small off grid  application specific additions to my grid tied system as an alternative to adding grid tied storage. Specifically a system to power a (or some) mini-splits to assist my 35+ year old undersized air conditioning during peak rates and declining production, 4-9 pm. Or a stand alone system for my pool equipment. If it's not too far OT I'd appreciate some comments on that - a blend of off grid and grid tied pv. Best of both worlds? Too many complications? I'm not looking to short change the utility but it does seem they need some help or a bit of relief till they figure out how to  fix their grid and have time to implement it. As long as there is a reasonable roi.

I have a new grid tied system and I don't think I would want my whole house to be off grid. I don't mind paying for grid infrastructure cost separate from electric use and appreciate the grid being my battery.

My system's size should cover almost all my annual usage but I was worried that the switch to tou rates would reduce my savings and increase the time for it to pay for itself (reduced roi) as my largest load (a/c) by far is peak summer rate during declining production. June had awesome overproduction which net metering banked for me. I guess I won't know the whole tally till July, August, September roll by.

I'm in almost the same boat. I have minisplits and right now 60% of my total consumption is HVAC but only about 40% is during sun hours. I already have an off grid aio and would like to use it to charge a battery for greater self consumption, so I'm also looking for the best way to implement this. There are wealthy people here who will say - "just buy 4 xw pros,two to use and two to store ,cos two is one and one is none" but I really can't afford to play in that sandbox so I need the poor man's option

 

[timselectric]

What's an xp pro?
Sounds expensive.

 

[1201]

What's an xp pro?
Sounds expensive.

Fixed. It IS expensive

 

[timselectric]

Fixed. It IS expensive

Yup
I'm cheap. lol

 

[wattmatters]

If it's not too far OT I'd appreciate some comments on that - a blend of off grid and grid tied pv. Best of both worlds? Too many complications?

Go have a look at the thread linked in my signature line. This is exactly what I have ended up with. Whether it makes sense for you depends on various factors. It's working for me.

I wish I had mini splits which I could run via my off-grid system but we have a reverse cycle ducted aircon system and it's power and energy consumption is a bit high for off-grid use so it is covered in the daytime by the grid-PV but draws from the grid at night. Mini splits were not an option for us due to the way the house is built.

 

[NCislander]

For the small “screw you money” they offer , I’m not interested in even gettin a check in the mail from those people…to much work to open the letter…I want to be totally be off their radar… I am nobody.. I don’t exist…they are nobody ..they don’t exist ..
I don’t wanna know them and don’t want them to know me…
that’s how I feel about sharks…

I tried to be sorta clear on my feelings here…..Do you kinda get my drift..?

Completely agree here.
The fewer people know what/where of my routines, the better. Hence why I don't bother attempting any kind of deduction.

 

[ksmithaz1]

Opinions are like *ssh*les, everone has one... So a bit long winded but IMNSHO,

The cheapest/fastest way to implement working Solar is on-grid with micro-inverters, depending on what your grid connection costs are (control boxes, electricians, inspectors, permits, etc). In this way you just dump all your excess solar output to the LPC when your demand is low, and the LPC buffers your demand when it exceeds your output. That being said, cost savings depends on how much you can lower your demand from the local power company, and how much they may give you for what you push to them. It's actually pretty good here in Arizona.

The minute you push batteries in the mix, if you still want to grid-tie, you may as well get one of the newer all in one's and skip the micro-inverters, just run your panels in series and get string voltages up. This really only helps you flatten your peak demand slightly unless you get enough inverter output to run your whole house. At this point, you can use PV to charge your batteries when your demand is low, and batteries to to cover when your demand is high. This is where I think it get's interesting, and less useful to pay for the additional expense of grid-tie & sell back.

I'm literally putting panels on the roof today/this weekend. It's 108F (3pm) so I quit until later. I will have 14KW of panels hooked to a pair of EG4 18K's. I have 30K of battery, the "18"K is PV input, they each have 12KW of output. I've been load testing, the setup struggles a bit starting the 4T A/C but with the soft-start kit, it just blinks, instead of browning-out for 500ms or so. Note: Grid tie would eliminate that issue. The power company has enough reserve joules, to keep the voltage from dropping too low.

To start with I will not be tied at all. I have enough 'solar/battery generation' ability to output 100A. So for now I have moved everything (All my loads) to a 100A (125 de-rated) panel and I have a 100A transfer switch with feeds from the grid, and from my solar inverters. The goal is to remove all peak usage, that is between 1300-2000 M-F, when in June and July the cost is a little under $0.25/kwh. Off-Peak is a hair over $0.08/kwh. To the point of the other poster, this is really a hobby. But in this case, I will just take myself off-grid as long as I have enough juice. Based on my testing, I can run 4 full hours from the batteries only (Charged off-peak from the grid ). My mean load is around 5kw, so at some point in the evening the PV output will drop below 5KW, and I'll have at least 4 hours before I need help from the grid, and that will definitely be well after 8PM, we have some sun until 7PM or so.

Now these 18K's fully support grid tie, and I MIGHT do something with that, but some things must happen before that is cost-effective. Mostly I'll need to actually produce electricity that I am not using, because I don't need a buffer. Pushing my own electrons at my loads is always going to be more cost effective than selling it to the LPC. 14K of panels with about 6 hours equivalent full sun/day is 84KWH at best. Last summer this time my daily usage was closer to 105kw/day based on my bill. That puts me about 20KWH short at best, reality is things are likely to be significantly lower, how much lower I will be finding out shortly.

For me, grid-tie/sell back woutld be after I double my panels and batteries, just to cover the meter charges and whatnot, so I can keep it as a backup. ie get my electricity cost to 0. This is going to be interesting. My July/Aug bills last year were very close to $400. The Winter peaks are 0500-0900,1700-2100 so those are going to be more interesting. I have an SBC running a bunch of sensors and relays to keep my peak demand under 100A. I will have to tie it into the inverters for a bit finer control come November. First upgrade is obviously more panels. Having Fun!

 

[Hedges]

Specifically a system to power a (or some) mini-splits to assist my 35+ year old undersized air conditioning during peak rates and declining production, 4-9 pm. Or a stand alone system for my pool equipment. If it's not too far OT I'd appreciate some comments on that - a blend of off grid and grid tied pv. Best of both worlds? Too many complications?

I would buy a used grid-tie inverter (e.g. Sunny Boy SWR 2500U or 5000US or whatever) and connect it behind the power switch of pool pump or A/C.
After switch turns on, it waits 5 minutes then backfeeds the grid. Sized no larger than your load, no net backfeed actually occurs.

Connect 2 PV strings, one tilted and oriented SE or SSE, the other SW or SSW.

The fancier version is find something that supports export limit with CT. Install like any other GT PV, and configure so it's export plus your existing system doesn't exceed your max allowed export.

 

[1201]

I would buy a used grid-tie inverter (e.g. Sunny Boy SWR 2500U or 5000US or whatever) and connect it behind the power switch of pool pump or A/C.
After switch turns on, it waits 5 minutes then backfeeds the grid. Sized no larger than your load, no net backfeed actually occurs.

Connect 2 PV strings, one tilted and oriented SE or SSE, the other SW or SSW.

The fancier version is find something that supports export limit with CT. Install like any other GT PV, and configure so it's export plus your existing system doesn't exceed your max allowed export.

Mini splits are variable load- can be 2500w or 40w so I'm not sure that would work so well with a mini split

 

[Hedges]

In that case, you'd like to feed PV DC directly to HV DC bus of VFD. but may be hard to keep voltage within range. A HV MPPT would be desired.

Are there PV direct units you might install, with AC powering them to the extent they drop below some voltage?

 

[wattmatters]

People may not like the limited credit they get for exporting energy but if it's going to do nothing else useful or be curtailed why would you not take it and provide some clean energy into the grid?

 

[Nobodybusiness]

People may not like the limited credit they get for exporting energy but if it's going to do nothing else useful or be curtailed why would you not take it and provide some clean energy into the grid?

Because people aren’t that altruistic.

 

[Hedges]

Hey, if we could do that as a charitable contribution to someone in need, so they received the power we delivered at no cost, we might even do that.
But not as a contribution to PG&E.

 

[45North]

Pacific Gas & Electric being one of 3 big power companies in California. Why are they so unpopular?

 

[ksmithaz1]

People may not like the limited credit they get for exporting energy but if it's going to do nothing else useful or be curtailed why would you not take it and provide some clean energy into the grid?

Because they want to charge you to give them your power? As long as there is no cost to me, I'm fine with it. In fact if it would just cover my meter charge ($20/mo here), that would be fine. Some people are saying their LPC's are a little goofy about taking their power. Keeping in mind the cost of the connection in the first place.

 

[timselectric]

As far as I know. The power companies don't allow the export credits to be applied to non metered fees.

 

[Ampster]

Pacific Gas & Electric being one of 3 big power companies in California. Why are they so unpopular?

Judging from this and other forums, I think all of the Investor Owned Utilitiess are unpopular. There are still municipal utilities that are not regulated by the CPUC and they all have rates which are less expensive that the IOUs. The CPUC is even less popular in my mind than the three IOUs they regulate.

 

[timselectric]

The MAN is always unpopular.

 

[45North]

The MAN is always unpopular.

Ok, now we're getting somewhere!
So it's not due to any specific actions or policies and more of a resentment of authority in general?
If that's the case then it seems that NOTHING they do would ever make some people happy.