Ive had solar for a year and now the utility company charges a demand fee... not cool.
- Thread starter vwaudiguy
- Start date
Plum Crazy Rob
Solar Enthusiast
Year 21 of pump and dump. Paid $2800 for FHP (now Bosch) no nonsense single stage system with cupronickel coil and desuperheater minus $600 utility rebate. Used existing home well and discharge to riverbottom - i do have an inexhaustible supply of sand filtered water at 20ft depth, back property line is the river 1/2 mile away. Figure $500 for DIY materials to install.
No problems ever. I did kill one Grundfos SQE pump, one PSC blower motor, and I delime minimum every other year with 5 gallon bucket of vinegar, and circulatory pump. Indeed, open loop CAN work.
This was prophesied in the good book - death spiral of the legacy grid
wheisenburg
Independent Solar Consultant
The important pieces of information to know for peak shaving are:
So if the peaks are large like 15 KW
If they last a long time say 10 hours in a day mainly at night
You will need 150 KWHs or $45,000 of batteries to fill that usage gap. That will be very expensive to fill with batteries/inverters. If you plan for 10 hours and the gap turn out to be 10:15 you will not gain anything, because your battery gave out before the peak ended. You will be charged anyway.
Gas Fire Place
This would reduce the need to run your resistive heat.
Just a thought, but since you are saying this issues is relatively infrequent when you have extremely cold weather, you might consider a gas fireplace. These are available in a variety of BTU outputs and efficiencies. It has the added benefit of giving you some emergency heating when the grid is down. Note that some of the newer systems use fully electronic control systems. Older systems worked like old water heaters where the required electricity was supplied by a thermocouple. So it may actually require batteries to turn it on when your power is down.
So, for about $7000.00 one of these could be installed in your house. If you don't have propane or gas and you don't want to get it installed, (it sounds like you are all electric) this is not an option. It is rather ironic that the hardest houses to take "Off Grid" are actually the all electric houses. Their electric power requirements are huge compared with houses that use some natural gas. My house has a natural gas furnace, water heater, and stove. It does have an electric dryer and wall oven, but usage of those can be managed. Would I cook a turkey when the grid is down and there is no sun? Probably not.
Before I had a full home back up, my plan was to use my gas fire place if the grid went down. Would it have heated my home as evenly as my furnace? No. Would it keep me reasonably comfortable and prevent the pipes from freezing in an emergency? Certainly.
One thing I am not sure about is this. Is this demand charge per month for your peak electricity for the whole year, or is it by the month in which the peak occurs? If this saves you 70 a month, it will take 8 years to pay back the cost. If the charge only applies to say the two coldest months where the resistance heat is being used, the pay back is 50 years.
Load Management
Rather than supporting peak usage through batteries and inverters, this would reduce the actual amount of energy being used at one time. For example if you want your house heater to have priority over your clothes dryer and water heater, you could program this into your device. Your water heater could run when the heater was not running. Maybe you make the range a higher priority than your heater. You can still cook, because the device will turn off the heater until you are done cooking.
This solution by Sol Arc seems like it would be a potentially great solution to your problem. The only issue is that they have been saying this is "coming soon" for 1.5 years. Apparently they are having challenges getting this out the door. I am just guessing, but my understanding is that for a 240 volt circuit it requires that two relays be paralleled together. Now when using 240 volts in a normal panel you need to provide a mechanical interlock to insure that BOTH hot leads are disconnected when you switch the breaker off.
The device has 14 circuits, so it can manage 14*120 volt circuits or 7*240 volt circuits by paralleling 2 circuits together. Now the problem would be that if this device was not configured correctly or there was some kind of a glitch, it could lead to only one leg of the 240 volt circuit being disconnected.
Backup Generator
Many commercial properties have "Load Shedding" agreements with the power company. If you could use a back up generator during days with extreme cold you would avoid the extra charge. I'm not sure this on makes sense unless a generator is already part of your plans as you will need a large one to support these loads.
Throwing expensive inverters and batteries at the problem may not be the best way to solve it.
- what is the size of the peaks
- what is the duration of the peaks
- what is the frequency (how many months would you see these peaks)
- what are the components that make up the peaks
So if the peaks are large like 15 KW
If they last a long time say 10 hours in a day mainly at night
You will need 150 KWHs or $45,000 of batteries to fill that usage gap. That will be very expensive to fill with batteries/inverters. If you plan for 10 hours and the gap turn out to be 10:15 you will not gain anything, because your battery gave out before the peak ended. You will be charged anyway.
Gas Fire Place
This would reduce the need to run your resistive heat.
Just a thought, but since you are saying this issues is relatively infrequent when you have extremely cold weather, you might consider a gas fireplace. These are available in a variety of BTU outputs and efficiencies. It has the added benefit of giving you some emergency heating when the grid is down. Note that some of the newer systems use fully electronic control systems. Older systems worked like old water heaters where the required electricity was supplied by a thermocouple. So it may actually require batteries to turn it on when your power is down.
So, for about $7000.00 one of these could be installed in your house. If you don't have propane or gas and you don't want to get it installed, (it sounds like you are all electric) this is not an option. It is rather ironic that the hardest houses to take "Off Grid" are actually the all electric houses. Their electric power requirements are huge compared with houses that use some natural gas. My house has a natural gas furnace, water heater, and stove. It does have an electric dryer and wall oven, but usage of those can be managed. Would I cook a turkey when the grid is down and there is no sun? Probably not.
Before I had a full home back up, my plan was to use my gas fire place if the grid went down. Would it have heated my home as evenly as my furnace? No. Would it keep me reasonably comfortable and prevent the pipes from freezing in an emergency? Certainly.
One thing I am not sure about is this. Is this demand charge per month for your peak electricity for the whole year, or is it by the month in which the peak occurs? If this saves you 70 a month, it will take 8 years to pay back the cost. If the charge only applies to say the two coldest months where the resistance heat is being used, the pay back is 50 years.
Load Management
Rather than supporting peak usage through batteries and inverters, this would reduce the actual amount of energy being used at one time. For example if you want your house heater to have priority over your clothes dryer and water heater, you could program this into your device. Your water heater could run when the heater was not running. Maybe you make the range a higher priority than your heater. You can still cook, because the device will turn off the heater until you are done cooking.
This solution by Sol Arc seems like it would be a potentially great solution to your problem. The only issue is that they have been saying this is "coming soon" for 1.5 years. Apparently they are having challenges getting this out the door. I am just guessing, but my understanding is that for a 240 volt circuit it requires that two relays be paralleled together. Now when using 240 volts in a normal panel you need to provide a mechanical interlock to insure that BOTH hot leads are disconnected when you switch the breaker off.
The device has 14 circuits, so it can manage 14*120 volt circuits or 7*240 volt circuits by paralleling 2 circuits together. Now the problem would be that if this device was not configured correctly or there was some kind of a glitch, it could lead to only one leg of the 240 volt circuit being disconnected.
Backup Generator
Many commercial properties have "Load Shedding" agreements with the power company. If you could use a back up generator during days with extreme cold you would avoid the extra charge. I'm not sure this on makes sense unless a generator is already part of your plans as you will need a large one to support these loads.
Throwing expensive inverters and batteries at the problem may not be the best way to solve it.
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ksmithaz1
Solar / EV Junkie
Power here is relatively inexpensive. They have different plans, but both SRP and APS require demand billing ($30 mon) if you grid-tie your solar. If not you can just do TOU or straight line billing. They have other oddball plans as well.
ksmithaz1
Solar / EV Junkie
'It is rather ironic that the hardest houses to take "Off Grid" are actually the all electric houses. Their electric power requirements are huge compared with houses that use some natural gas.'
Indeed but if you are using NG you are only off the Electrical grid, not the Utility grid. So if you want to be "Off Grid" you need to be running more solar or a wood stove or something not piped in. If you truly want to be "Off-Grid", as in not dependent on a 3rd party utility, all electric with some wood stove emergency backup is going to be somewhat simpler, but you will have to build it out for demand which is going to be pricey.
Indeed but if you are using NG you are only off the Electrical grid, not the Utility grid. So if you want to be "Off Grid" you need to be running more solar or a wood stove or something not piped in. If you truly want to be "Off-Grid", as in not dependent on a 3rd party utility, all electric with some wood stove emergency backup is going to be somewhat simpler, but you will have to build it out for demand which is going to be pricey.
oh ok. my friend who has solar in phoenix showed me a bill and it had tou, demand and usage. Ive never seen so many line items on a bill
OzSolar
Whatever you did, that's what you planned.
A few ironies that I think are worth mentioning:
REC (Rural electric COOP's) are member owned and take every chance they get to proudly declare that are very member centric, but this continued behavior clearly demonstrates that they want to do anything but what's best for their members.
IOU (Investor Owner Utilities) are publicly regulated. In general, that means that they are tasked with delivering the lowest cost energy to its customers and in exchange for that they are guaranteed a profit. I think that if regulators did their job, I think the utilities would have a hard time have proving that these rates structures and added result in the lowest cost energy.
At what point does 20/20 etc. get involved in this? Seems like a great story to me.
wheisenburg
Independent Solar Consultant
I guess I am one of those people that wants to plan for the most common outages, and not necessarily every possible scenario. My system is best described as grid tied with some emergency backup capability. Having enough backup electricity to run without the grid is much more affordable when you have a gas stove, hot water heater, and furnace. Trying to heat a house in -5 degree temperatures with resistive heat coming from batteries, just isn't very cost effective. Solar is actually great for running A/C systems since the demand meets up well with the available power production. Trying to run a heat pump or resistive heat off solar when you are fairly far north and winters tend to have long periods of clouds just doesn't work very well. You get the least power when your demand is highest.
I think it is safe to say that Natural Gas is more reliable than electricity. Propane is better still. For 2-3 months a year even with not too many huge electric loads, my solar is not going to produce enough power to run everything. I am about 300 KWHs short in Dec, Jan, Feb. I would need to double my array from 12,500 to 25,000 watts to make enough power in those months. At $2.50 a watt this would run $30,000 for that extra $150.00 of electricity I need in the winter. If the grid is down for a long time, I would need some supplemental power from a generator. Even most fully off grid homes have generators available for times when solar production is low. I have full 1 to 1 net metering here and the credits roll over from one month to the next. So my winter electricity is paid for by my summer over production. Over the course of a year when the grid is working my system over produces, so I actually get cash back once a year in June when they do their "True up". Adding more hardware doesn't make sense for me.
The thing is with the scenario outlined here, there is a very good chance that no matter how many solar panels and batteries you threw at this problem, at some point they would be exhausted. If the resistance heat turned on for any one 15 minute period, you would end up paying the demand fee anyway. Given this might happen 2-3 times a year, there is no case to be made for trying to solve this problem with solar. The cost of the equipment vs the demand fee makes it totally impractical.
I also don't have a doomsday bunker buried in my back yard.
ksmithaz1
Solar / EV Junkie
You should work on that. . .
At -5F I think you could handle all-electric with the right HVAC equipment, depends on how much lower than that you need to go. Some of the guys here are probably darn close, to the 1 or 2 days of supplemental power, but indeed, from time to time solar power is just not going to cut it even with an exorbitant expenditure of capital.
seneysolar
Solar Addict
I see alot of off grid houses and cabins here in northern michigan. None try to heat with electricity. The simple answer is its too expensive and will still result in disappointment.
The common item EVERY SINGLE OFF GRID HOUSE HAS is wood heat. Woodstove or even outdoor wood boiler. Circulation of air and water is easy to run on solar.
Runner up would be propane or natural gas furnace. Even mentioned above, a freestanding propane fireplace. (I have one, its fantastic)
Sure on paper you can get the numbers to work in your favor but that wont be reality. The only way to heat with electricity is to waste alot of it. The OP's electric bill proves this.
The common item EVERY SINGLE OFF GRID HOUSE HAS is wood heat. Woodstove or even outdoor wood boiler. Circulation of air and water is easy to run on solar.
Runner up would be propane or natural gas furnace. Even mentioned above, a freestanding propane fireplace. (I have one, its fantastic)
Sure on paper you can get the numbers to work in your favor but that wont be reality. The only way to heat with electricity is to waste alot of it. The OP's electric bill proves this.
Ryushin
Solar Enthusiast
I'm late to the party and I only read the first two pages. I have a demand rate between 4-8PM of $3.00. I have my Sol-Ark 15K set to not utilize any grid power during that time and to use solar and/or batteries during that time. Reading your first post, the demand charge is set to 15 minutes during any 24x7 day for the entire month? Is that correct? Ludicrous in my mind. Totally a money grab from what I see.
If that is indeed the case, getting away from that will be hard. It's bad enough it actually might be cheaper to run on a generator for those days you don't have solar and your batteries are empty. I see an EG4 18K PV or a Sol-Ark 15K in your future.
If that is indeed the case, getting away from that will be hard. It's bad enough it actually might be cheaper to run on a generator for those days you don't have solar and your batteries are empty. I see an EG4 18K PV or a Sol-Ark 15K in your future.
OzSolar
Whatever you did, that's what you planned.
You get cash back? That would be the first time I've ever heard of that.
Here in Missouri we get 1 for 1 during the month but any excess is carried forward at wholesale which, as you probably already know, is ~1/5th of retail. On top of that our annual true up is zeroing out any excess at no cash or credit.
What they are trying to move to is no net metering so any excess is immediately credited as wholesale.
vwaudiguy
New Member
Yes the demand is a 24x7 thing starting in April for me... a money grab is the best way to put it... I would love to have the Sol-ark 15k..
vwaudiguy
New Member
-5 is as low as we got this winter.. it lasted about 2.5 days... I could run the generator to supplement those days in the future if need be.. I just need a heat pump that works well in the cold
vwaudiguy
New Member
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ksmithaz1
Solar / EV Junkie
Again, if you are grid tied, you have to deal with demand for what should be obvious reasons, because they are giving you credits for any backfeed, and their desire is for you to help clip peak demand. My objective is for the charges to be something less than $25/mo. I'm pretty much at zero since the 15th, I expect that this weekend, 1/15-2/15 was my worst month. I produced my first bit of solar in June, but was fiddling around until mid-July. With the extra batteries, I should be able to drop even lower, more panels before June to pick up the EV needs.
wheisenburg
Independent Solar Consultant
It is a great deal. Due to Three Mile Island we have had cheap reliable power here in this part of PA. Because of that, there has been very little solar. They shut TMI down a couple of years ago and our rates have gone up. My annual net metering true up isn't huge. For 2023 I produced 2.5 MWHs more than I consumed, at $0.18 KWH that should be around $450.00. There is a $15.00 a month connection fee, so the true up will more than cover that for a year.
The last couple of years solar has really picked up in this area. I was the first in my neighborhood to get it. Now another 5 people have it. This very favorable deal for solar won't last, but I should still be grandfather in for 15 years.
wattmatters
Solar Wizard
Demand charges are now part of the default tariff plans for new residential connections in significant parts of Australia, notably SE Queensland and the major metro areas in NSW. It has nothing to do with solar PV, with one exception, that being if your meter needs to be upgraded due to installing a new grid-tied solar PV installation, then you transfer to the new default tariff structures. You can however opt out and move to a regular time of use tariffs (TOU).
In other regions where there are demand tariffs they are usually opt-in, with TOU being the default.
In my region the options are TOU (default) or Demand+TOU, where on the Demand+TOU tariff the difference between peak and off-peak consumption tariffs is much less.
People do hate demand tariffs here, partly as they are relatively new for residential, and partly because people are crap at maths and not even electricity retailer support staff can explain them.
It's not helped here by the way the tariff is presented.
e.g. instead of saying peak demand tariff is (say) $4.50/kW/month which makes sense (i.e. your peak demand for the month is X kW, so multiply that by the demand tariff), here it's expressed as 15c/kW/day (i.e. X kW x 15c/day x number of days in the month). The peak demand is only assessed during the peak demand window. It's little wonder people don't get it.
In the next year or so new types of tariff structures will begin being offered and become the default for new connections and meter changes, with solar soaker tariffs (off-peak middle of the day) and rewards for exporting energy during peak periods. I did a quick look at the average wholesale price for the whole year 2023 in NSW by 5-min intervals, and it's little wonder why:
We already are starting to get retailers offering free power for 2-3 hour periods in the middle of the day. I've just signed up for one. It's only 2-hours free each day on weekends, but heck in those four hours I can ramp the home battery charge rate to the max, put 150km of range into the car and maybe delay my water heater until then as well. Obviously I have to chew up my PV generation first but that's OK.
There are other plans with a free period everyday, but alas the balance of their tariffs don't work for us.
In other regions where there are demand tariffs they are usually opt-in, with TOU being the default.
In my region the options are TOU (default) or Demand+TOU, where on the Demand+TOU tariff the difference between peak and off-peak consumption tariffs is much less.
People do hate demand tariffs here, partly as they are relatively new for residential, and partly because people are crap at maths and not even electricity retailer support staff can explain them.
It's not helped here by the way the tariff is presented.
e.g. instead of saying peak demand tariff is (say) $4.50/kW/month which makes sense (i.e. your peak demand for the month is X kW, so multiply that by the demand tariff), here it's expressed as 15c/kW/day (i.e. X kW x 15c/day x number of days in the month). The peak demand is only assessed during the peak demand window. It's little wonder people don't get it.
In the next year or so new types of tariff structures will begin being offered and become the default for new connections and meter changes, with solar soaker tariffs (off-peak middle of the day) and rewards for exporting energy during peak periods. I did a quick look at the average wholesale price for the whole year 2023 in NSW by 5-min intervals, and it's little wonder why:
We already are starting to get retailers offering free power for 2-3 hour periods in the middle of the day. I've just signed up for one. It's only 2-hours free each day on weekends, but heck in those four hours I can ramp the home battery charge rate to the max, put 150km of range into the car and maybe delay my water heater until then as well. Obviously I have to chew up my PV generation first but that's OK.
There are other plans with a free period everyday, but alas the balance of their tariffs don't work for us.
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