What's so bad about selling to utility wholesale?

[wattmatters]

5 year cost recovery is great. So do people close grid tied or off grid systems?

99.5% of systems would be grid tied and 1/3rd of homes have a PV system. ~3% of those with PV have a battery.

Off-grid is niche, usually where grid isn't an option. Very, very few would choose to be off-grid where grid is available. DIY is even more of a niche.

Professionally installed rooftop grid-tied PV systems (including everything) here cost US$0.50-0.80 per watt.

While PV installations have been growing strongly for many years and the average size of systems is also getting larger, there will be another spurt of interest in getting solar PV as from today there has been a sharp rise in tariffs. Batteries however are still limited in number - mainly because the cost of a grid tied battery is still way too expensive to make financial sense (DIY grid tied PV isn't really an option). It's still mostly confined to those who want energy security, or just like having the tech because they can and saving money isn't the objective.

The grid market operator expects we will approach 2/3rds of homes with rooftop PV.

 

[fromport]

I have 66kW of battery inverter, 167kW of GT PV inverter, 12kW of SCC, 62kW of PV panels, 25kWh of battery.

I don't expect it to every pay for itself. And I'm still on-grid. With natural gas available.

So in 2025 when they threaten to "tax" you based on income for heaving a utility connection, btw: for each location, so if you own multiple properties you get dinged multiple times. Would you still not consider going off-grid by then ?

 

[wattmatters]

Any chance we can get back to the thread topic about selling to the grid wholesale?

 

[1201]

99.5% of systems would be grid tied and 1/3rd of homes have a PV system. ~3% of those with PV have a battery.

Off-grid is niche, usually where grid isn't an option. Very, very few would choose to be off-grid where grid is available. DIY is even more of a niche.

Professionally installed rooftop grid-tied PV systems (including everything) here cost US$0.50-0.80 per watt.

While PV installations have been growing strongly for many years and the average size of systems is also getting larger, there will be another spurt of interest in getting solar PV as from today there has been a sharp rise in tariffs. Batteries however are still limited in number - mainly because the cost of a grid tied battery is still way too expensive to make financial sense (DIY grid tied PV isn't really an option). It's still mostly confined to those who want energy security, or just like having the tech because they can and saving money isn't the objective.

The grid market operator expects we will approach 2/3rds of homes with rooftop PV.

Wow. .80 per watt is very affordable. The 2/3rds prediction doesn't surprise me

 

[fromport]

Any chance we can get back to the thread topic about selling to the grid wholesale?

I just got my true-up last month. I overproduced and put a considerable amount of kWh back into the grid.
After deducting my monthly subscription fees paid over the whole year, I got paid $0.07/kWh for every kWh I put in the grid.
With the costs of what I paid for my DIY PV setup my setup costs would be paid back within 6 years from that if nothing changed.
But I also have free electricity.
And having no gas, house everything electric and driving 15K miles/year with the EV I think that is an excellent situation to be in.
However, I will get kicked out of NEM2.0 next year, and then everything changes.
With NEM3.0 in california, selling to the grid becomes not a profitable option.

 

[Zwy]

I just got my true-up last month. I overproduced and put a considerable amount of kWh back into the grid.
After deducting my monthly subscription fees paid over the whole year, I got paid $0.07/kWh for every kWh I put in the grid.
With the costs of what I paid for my DIY PV setup my setup costs would be paid back within 6 years from that if nothing changed.
But I also have free electricity.
And having no gas, house everything electric and driving 15K miles/year with the EV I think that is an excellent situation to be in.
However, I will get kicked out of NEM2.0 next year, and then everything changes.
With NEM3.0 in california, selling to the grid becomes not a profitable option.

You are lucky you were able to get into NEM2.0.

As I stated previously, nothing will stop them from changing the rules/agreement.

Are you planning on battery storage?

 

[fromport]

You are lucky you were able to get into NEM2.0.

indeed

As I stated previously, nothing will stop them from changing the rules/agreement.
Are you planning on battery storage?

I recently invested in hybrid inverters and batteries. Currently 24kWh online and 40kWh more available in a few months.
I need to get even more storage and more PV to test going off grid in the future. I still have 2024 to test for that.

 

[wattmatters]

Wow. .80 per watt is very affordable.

That would be an expensive system. Average price is US$0.65/W.

Means selling to the grid easily covers costs, while import replacement is where big savings are made. Really only need to self consume about 30% of consumption to have a fairly rapid recovery of costs.

Basic export tariffs are in the US$0.033 to US$0.10 per kWh range (although in Western Australia they are US$0.02 / kWh, US$0.067 after 3PM). Import tariffs meanwhile are in the US$0.13 to US$0.43 per kWh range depending on time of day.

Selling wholesale is far more risky and is really only worthwhile considering if you have an export capable battery system and a means to cleverly control it.

One thing we may see is some use of V2G. It won't be a massive thing and confined to homes with a suitable set up but I expect we'll see more of it in the years ahead here. At the moment however approved V2G capable controllers are either non-existent or very expensive but we can hope they will become a more competitive option as EV adoption picks up (we lag the rest of the world on that).

 

[Cheap 4-life]

currently your power meter counts electric coming from either direction as billable so to have a grid tied system you need the electric company to install a meter that counts down when you're generating electricity..

There is grid tie zero export inverters and hybrids that zero out the electric bill without exporting

 

[1201]

I just got my true-up last month. I overproduced and put a considerable amount of kWh back into the grid.
After deducting my monthly subscription fees paid over the whole year, I got paid $0.07/kWh for every kWh I put in the grid.
With the costs of what I paid for my DIY PV setup my setup costs would be paid back within 6 years from that if nothing changed.
But I also have free electricity.
And having no gas, house everything electric and driving 15K miles/year with the EV I think that is an excellent situation to be in.
However, I will get kicked out of NEM2.0 next year, and then everything changes.
With NEM3.0 in california, selling to the grid becomes not a profitable option.

Aren't you grandfathered into nem 2 for 20 years?

 

[1201]

That would be an expensive system. Average price is US$0.65/W.

Means selling to the grid easily covers costs, while import replacement is where big savings are made. Really only need to self consume about 30% of consumption to have a fairly rapid recovery of costs.

Basic export tariffs are in the US$0.033 to US$0.10 per kWh range (although in Western Australia they are US$0.02 / kWh, US$0.067 after 3PM). Import tariffs meanwhile are in the US$0.13 to US$0.43 per kWh range depending on time of day.

Selling wholesale is far more risky and is really only worthwhile considering if you have an export capable battery system and a means to cleverly control it.

One thing we may see is some use of V2G. It won't be a massive thing and confined to homes with a suitable set up but I expect we'll see more of it in the years ahead here. At the moment however approved V2G capable controllers are either non-existent or very expensive but we can hope they will become a more competitive option as EV adoption picks up (we lag the rest of the world on that).

I couldn't even get it installed here diy for less than $1 per watt. I'm jealous. So how do people size systems over there? To zero out the bill?

 

[JRH]

You are lucky you were able to get into NEM2.0.

As I stated previously, nothing will stop them from changing the rules/agreement.

Are you planning on battery storage?

Dealing with the “ grid big whigs “ is like playing poker with someone who has more money than you- can see what cards you have - and can change the rules of the game to suit his needs to win…in the end you have no chance..
And it’s just Gona get worse… …….get prepared… stay prepared…have an exit plan…
J.

 

[wattmatters]

I got paid $0.07/kWh for every kWh I put in the grid.

That would be a pretty decent feed in tariff here.

Our 11 kW 3-phase grid tied PV reduced our bills by A$3,200/year and cost $A$12,800 to have installed. I'll let you guess when we installed grid-tied PV:



The more recent drop in bills is mostly due to the addition of some off-grid PV and battery, as well as increasing self consumption by PV diversion to water heater. But we will never make the sort of gains we did from the initial grid tied PV system and undertaking reasonable steps to manage consumption.

Wholesale pricing is not on my radar as my battery, being off-grid, cannot export to the grid.

Keeping momentum on bill reduction is getting harder with the recent very large increase in tariffs, so the less we need to import, the better:



Considering we added a second dwelling, it's not too bad. We are now generating more than we consume:


But I do want to add another 2-3 kW of off-grid PV. I have no scope to increase the grid tied PV system.

 

[wattmatters]

So how do people size systems over there? To zero out the bill?

In general they fit as much as the roof will sensibly take or the local distribution company permits, or their budget allows. Average residential grid tied PV systems installed today are in the 8-13 kW range. People are trying to give themselves some production headroom for future demand changes, most notably a transition away from fossil energy for space and water heating and for motor vehicles.

 

[Ampster]

Utilities don't want to be your battery anymore, they will get the rules changed for their advantage

I agree and those days are long gone in California except as a seasonal battery where the True Up is on an annual basis. I don't mind a reasonable fixed fee to cover that and support upgrades to the grid.

 

[1201]

That would be a pretty decent feed in tariff here.

Our 11 kW 3-phase grid tied PV reduced our bills by A$3,200/year and cost $A$12,800 to have installed. I'll let you guess when we installed grid-tied PV:

View attachment 155198

The more recent drop in bills is mostly due to the addition of some off-grid PV and battery, as well as increasing self consumption by PV diversion to water heater. But we will never make the sort of gains we did from the initial grid tied PV system and undertaking reasonable steps to manage consumption.

Wholesale pricing is not on my radar as my battery, being off-grid, cannot export to the grid.

Keeping momentum on bill reduction is getting harder with the recent very large increase in tariffs, so the less we need to import, the better:

View attachment 155202

Considering we added a second dwelling, it's not too bad. We are now generating more than we consume:

View attachment 155204
But I do want to add another 2-3 kW of off-grid PV. I have no scope to increase the grid tied PV system.

Wow, huge drop in cost. I can see why it's so popular in Australia.

So how are you incorporating the off grid pv and battery into the whole system? I'm guessing a separate panel powered by the off grid inverter? Are you sizing it to power that panel 24 7? Or switch to grid at some point when battery is low?

 

[wattmatters]

So how are you incorporating the off grid pv and battery into the whole system? I'm guessing a separate panel powered by the off grid inverter? Are you sizing it to power that panel 24 7? Or switch to grid at some point when battery is low?

AIO inverter feeds a small off-grid panel. That in turns feeds the main service panel via a transfer switch. I generally leave the transfer switch in the off-grid supply position. My board is then split between "essential" and "non-essential" loads. The off grid supply covers the essential loads while the rest are grid supply only (which the grid-tied PV still covers during the day).

The AIO provides power 24x7 and swaps between solar/battery and utility first modes using automations I have set up in Home Assistant. In the day it operates in utility first mode passing through grid power, which is actually coming from my grid-tied PV array. Meanwhile the off-grid array is dedicated to charging the battery. At night the system automatically switches over to supply the home from the battery.

With the AIO's AC input I use the grid PV array to provide supplemental charging support for the battery should the off-grid array not be able to complete a full charge. This tends to happen during the Winter months, not so much in the Summer half of the year. Other automations control when and how much supplemental charging is used. Idea is to not use any more grid-PV for charging than is necessary, IOW maximise what the off-grid PV is capable of supplying.

This way I don't overly sacrifice the credit for exporting to the grid if I don't need to. This shows the average daily value of the battery, split by when discharging occurs, and also showing the cost of supplemental charging (foregone export credit).


The average daily value of battery discharge went up in April due to an increase in tariffs. They've just gone up again, quite sharply so I am expecting the daily value to remain at least where it is for June.

 

[Hedges]

Why?!

Because.

 

[Hedges]

So in 2025 when they threaten to "tax" you based on income for heaving a utility connection, btw: for each location, so if you own multiple properties you get dinged multiple times. Would you still not consider going off-grid by then ?

Have to consider. $93/month is a bit over $1k/year. My simple math says equivalent to $10k net present value (without doing a proper finance calculation). Times each property of course.

I could put in enough battery (at same or greater cost) to probably get by most of the time, assuming no electric heat. So use gas not electric? Gas bill went through the roof last year for one property (before it was mine.) Given NEM 2.0, paying $93/month to store electricity for winter may still be worthwhile. Hope it gets beaten back, just like earlier NEM 3.0 proposal did.

Then there is the reliability, support, convenience of the grid. And renters. So I think I should keep the grid and try to use PV for increased uptime and shaved power bills.

 

[Hedges]

Because.

If I also put PV on my mountain acreage (I won't), then I could almost make use of it all. Would need more battery.

I try to buy new old stock equipment by the pallet, get a number of inverters for the MSRP of one or two. So by the time I get one system running I haven't spent extra, and I have about 3x the equipment as spares.

I'd like to be able to use Sunny Island for peak shaving, could probably do that by using "grid as generator" during peak times, but I think that would suppress backfeed if I have surplus. It may take external control to accomplish.