Duke Energy SC - New rates for grid tied export

[Q-Dog]

That's a good point, but, honestly, if this is the trend and net metering is just going to get worse, it's probably not worth the hassle. I'm really not sure that without a huge solar array I'd pay less on the net metering plan today. Might be better to load shave and then, when prices get more affordable, add batteries to allow me to shave even more effectively. The good news, our primary consumption is really heat and AC; we both WFH, so our spending on both is generally highest during the day. For my application, I suspect that keeping my current plan and reducing usage the electric company sees, even if it means I under produce at times, might be the best way to go.

Problem is, I was thinking about doing a direct AC couple using microinverters. I'm not sure that's the best way to go if I may add batteries in the future, might be better to go down the route of something like an EG4?

A solar heat pump could reduce your daytime grid power use ... and you wouldn't have to tell the power company or pull any permits to install it.

 

[Overtaxed]

A solar heat pump could reduce your daytime grid power use ... and you wouldn't have to tell the power company or pull any permits to install it.

Yeah, I could do indvidual device solar, but, honestly, I see that as even more a waste than having a whole home setup and underproducing panels. Also, I have 3 heat pumps and 2 of them are almost brand new, so.... Yeah, not exactly a good ROI there.

I'm going to talk to them again this morning and see if there's an issue with solar w/o changing the rates if I don't infeed any power. I can't imagine why there would be, a solar heat pump is the same exact thing, a generation source, connected to the grid, but without the ability to backfeed.

That said, just because it "makes sense" doesn't mean that's how it is!

 

[Q-Dog]

None of it is a waste if it makes your life better. And having lights and power (and quiet) when the grid fails makes my life better. Plus, I'm happy to pay a little more to be less dependent on the power company.

 

[Overtaxed]

None of it is a waste if it makes your life better. And having lights and power (and quiet) when the grid fails makes my life better. Plus, I'm happy to pay a little more to be less dependent on the power company.

I already have a generator, and my grid is pretty darn reliable. This is all about my 4-500/mo electric bill and trying to pare that back a bit. If I can't save money, I'm not going to spend days doing the work and 1000's on the materials. I enjoy solar and electrical work, but not enough to spend that much money just to say I have it.

 

[Q-Dog]

I already have a generator, and my grid is pretty darn reliable. This is all about my 4-500/mo electric bill and trying to pare that back a bit. If I can't save money, I'm not going to spend days doing the work and 1000's on the materials. I enjoy solar and electrical work, but not enough to spend that much money just to say I have it.

Fair enough. But if I never have to fire up the loud gas generator ever again I would be happy ... and I spent extra for a quiet Honda.

 

[Overtaxed]

Fair enough. But if I never have to fire up the loud gas generator ever again I would be happy ... and I spent extra for a quiet Honda.

Yeah, quiet isn't their strong suit. I have a small inverter generator that's pretty reasonable, but, still, compared to the hum of an inverter, it's deafening. And my "big dog", well.. It's a 25KW PTO generator that I couple to one of our tractors. You can imagine what that sounds like. I have a 200A hookup for it on the side of the house, but, honestly, I've never used it in the ~10 years we've lived here to power the house. Our outages have never been long enough to go through the hassle of connecting it to the tractor and hooking it up. Nice to have if we need it, enough to power absolutely everything, AC's, heat, etc, but it's a backup to the backup.

 

[740GLE]

I’d say do an energy audit first see where that $4-500/mo is going.

So if you already have mini splits and they are your heavy hitters, you could get an AIO that is grid tied with zero export and minimal battery, run the mini splits off it it during daylight zero grid need, the use grid at night as needed, you’d prob be able to cut your usage in half if not more. Would you have panels that aren’t fully utilized sure, but PV is cheap and as you monitor load/generation production, you could toss more “grid load” on to the AIO.

 

[Osmethne]

I'm almost afraid to ask. One of those "don't open this can of worms" type questions. Maybe I'll use an Internet phone and call in with my neighbor's address.

I guess part of me wonders if they even need to know. I'd need to get it permitted and have the electrical inspector out, but, beyond that, not sure why Duke would even have a "say" in it, right? Simple example, I can hook up my RV at home and "load shave" on my 50A plug, in fact, I do it every day by "Ignore AC input" and let the inverter carry the load from the solar/battery.

This is my understanding of it. Your electric company sells you power. They're classified as a public utility which means they have no say over what you do with that power. Could be powering a meth lab. Could be charging 60kwh of batteries. It doesn't matter. Getting permission to charge batteries with grid power makes about as much sense as getting permission to run 3 refrigerators.

Backfeeding is a different story. There's the safety and integrity of the grid to consider. So if you export energy then you need to play by their rules regarding that.

I don't know if you need an electrician to approve anything if you're doing it yourself, assuming you know what you're doing. If you plan on mounting the panels on the roof of a house then there's city codes to consider.

 

[740GLE]

Only down side is the TOU all utilities will be going towards.

Remember “flatten the curve” of early 2020? Yeah applies to grid management as well.

 

[Sanwizard]

Been considering solar on the house (the RV already has a full compliment) for some time now. I called up Duke this morning and wow, they've figured out a great way to stop more solar from coming into the system!

My current rate is ~11c/kwh on what they call "RS" (Residential Service).

For solar, they install a bi-directional meter and move you to a rate called R-STOU (Residential Solar, Time of use). This has variable rates, but summing up (full details for anyone who's interested linked below)

Critical Peak - 27c/kwh
Peak - 17.5c/kwh
Off peak - 11c/kwh
Super off peak - 8.5c/kwh

Peak: 6AM-9AM; 6PM-9PM
Off peak: All hours not in peak or super off peak
Super off peak: 12AM-6AM, March 1-Nov 30th

If you look at the peaks, those are times when solar is basically at 0w and your electric consumption is likely to be high, morning getting ready for work and right after work until you go to sleep. Also, that "critical peak" is at the company discretion, no more than 20 day/yr.

So, summing all this up, I'm thinking solar might not make a lot of sense because I'd have to give up my good rate to get it.

I'm wondering if anyone else is in this situation and if you've done something like a "zero export" system to get around it. If I don't ask for a bidirectional meter, and I don't export any power, can't see why Duke would even need to know I have solar (still need permits from the town, of course), right?

My current rate plan:

https://www.duke-energy.com/-/media/pdfs/for-your-home/rates/electric-sc/scschedulere.pdf?rev=cedcf3d7929c475a8942e85cc37a089d

Solar plan with Duke for SC:

https://www.duke-energy.com/-/media/pdfs/for-your-home/rates/electric-sc/scschedulerstou.pdf?rev=4a416b90d0ba4cb0bae67252ab4ecfee

I have Dominion energy. The house I bought had grid tied solar, but the contract had expired. The home was empty while the owner had it on the market. I did NOT want a contract with Dominion, and figured any generation would just let me use almost zero power from the grid.

Nope. Once I moved in, they were CHARGING me for the power I made! The meter only spun one way, and saw my generation as power used from the grid. That PISSED me off, but they said the only way to fix it was with a bi directional meter and solar contract.

Make sure your not in a similar situation with Duke.

 

[Overtaxed]

I have Dominion energy. The house I bought had grid tied solar, but the contract had expired. The home was empty while the owner had it on the market. I did NOT want a contract with Dominion, and figured any generation would just let me use almost zero power from the grid.

Nope. Once I moved in, they were CHARGING me for the power I made! The meter only spun one way, and saw my generation as power used from the grid. That PISSED me off, but they said the only way to fix it was with a bi directional meter and solar contract.

Make sure your not in a similar situation with Duke.

I suspect I would be if I exported without a new meter. What I'm thinking is going with a system that I can setup for "zero export", basically if the panels are producing 10KW and I'm only use 5KW, the other 5KW is waste.

I'm trying to avoid any "new contract" with the power company, they all look worse to far worse than what I have today. I'd like to keep my existing rate but use less power because I generate some of my own. Sell back will never be scalable for the power company, it's only a matter of time until they stop it entirely or allow it, but only at 0/kwh. My FIL has a "net" contract in NJ, he buys at ~15c/kwh and sells at the same rate. That's completely economically unsustainable, but.. Well, good for him!

I don't know if you need an electrician to approve anything if you're doing it yourself, assuming you know what you're doing. If you plan on mounting the panels on the roof of a house then there's city codes to consider.

We do have code for electrical work around here, but, honestly, it's pretty much just a cursory look over; 50A breaker on 12G wire, he's gonna fail you, but as long as your breakers are sized right, your lugs are torqued, you have neutral and ground bonded or separated (depending on the panel) and there's no ground faults, you'll pass.

Thankfully, we're almost entirely without building codes. One of the huge advantages of living in the country. Not so nice when your neighbor decides to let their carport fall down (for the past 5 years), but real nice when you want to do something to your house. I built a 2400sq/ft barn on the property, went in to pull a permit and the lady behind the desk did one of those "You're not from around here" looks and explained, very nicely, "We ain't here to tell you what you can do with your land, go build your barn". Love it!

 

[Overtaxed]

Only down side is the TOU all utilities will be going towards.

Remember “flatten the curve” of early 2020? Yeah applies to grid management as well.

You can't fault them. The more solar on the grid, the more lopsided it will be, they'll have plenty of power when the sun shines and lots of idle capacity. That idle capacity needs to be paid for somehow, which will come in the TOU rates. Batteries are nowhere near the scale (or cost) they need to bank power, and, honestly, when they are, there will be a very different problem (people like me and many on this forum just cutting the cord entirely).

I understand their problem, but I'm not going to make it my problem.

 

[cs1234]

A solar heat pump could reduce your daytime grid power use ... and you wouldn't have to tell the power company or pull any permits to install it.

A solar heat pump would count as an hvac unit and require a permit here in Texas, from the city.. boy howdy. You need a permit to replace a hot water heater also, what's up with that? Not to install one, but to replace one you already have.

 

[740GLE]

Life free or Die, not so much in Texas I see.

 

[Overtaxed]

A solar heat pump would count as an hvac unit and require a permit here in Texas, from the city.. boy howdy. You need a permit to replace a hot water heater also, what's up with that? Not to install one, but to replace one you already have.

Rural life is calling.

I used to live in a community where I, literally, had to apply for permission (HOA) to repaint my door (the same color!!). Now I can build a barn bigger than many houses without a single permit? Freedom is a wonderful taste, especially when you've spent most of your life (as I had before we moved here) in an area where you have so litle of it.

 

[cs1234]

Life free or Die, not so much in Texas I see.

City permits, so I suppose I could just somehow raise a ruckus and get it changed. Be the change I want to see and all that.

 

[740GLE]

You can't fault them. The more solar on the grid, the more lopsided it will be, they'll have plenty of power when the sun shines and lots of idle capacity. That idle capacity needs to be paid for somehow, which will come in the TOU rates. Batteries are nowhere near the scale (or cost) they need to bank power, and, honestly, when they are, there will be a very different problem (people like me and many on this forum just cutting the cord entirely).

I understand their problem, but I'm not going to make it my problem.

How much battery would one need to carry load from say 6pm until 8am? 40kwh of battery storage isn’t that bad especially if you DIY, about 10k?

 

[Osmethne]

Rural life is calling.

I used to live in a community where I, literally, had to apply for permission (HOA) to repaint my door (the same color!!). Now I can build a barn bigger than many houses without a single permit? Freedom is a wonderful taste, especially when you've spent most of your life (as I had before we moved here) in an area where you have so litle of it.

I've lived in an HOA before, never again! You don't have to leave the city to get away from those though.

 

[Overtaxed]

How much battery would one need to carry load from say 6pm until 8am? 40kwh of battery storage isn’t that bad especially if you DIY, about 10k?

In the summer, not that much. In the winter, a lot (heat pumps). We use around 3,000Kwh per month when it's really cold out. I'd think that 40KWh would be enough to get me through most nights. And I guess I could go on TOU and start playing some real games (charging the battery when the rate is low, then switching to battery when the rates go up), but, honestly, I'm not THAT motivated. I'd like to do solar to save some money, not to have my home power become a science/economics project.

The funny thing, my area is served by the Monticello nuclear facility. Sure that's not helping my case, they can produce the power at a marginal cost approaching 0 dollars, they really don't want my power.

 

[740GLE]

Just because you’re next door to a large power plant doesnt mean the grid is connected in a way you are reviving power from it. Nukes typically have multiple transmission lines of high voltage, >230kv, to step down the voltage to run along yours street it may take 100 miles plus of lines 2-6 substations for that power to end up at your house.

But I digress.

3000kwhr/month is a nice heavy hitter!! Knowing your load in winter is still high (less than ideal PV generation) it’ll be very tough to mitigate.