Worth switching to net "time-of-use" metering for grid-tie solar system in NY (ConEd)

[MrBoylan]

Still murky

Hey CB, any updates?

I recently got a PV installation on my house here in NYC (although mine is larger at 7.194kW) and I'm currently debating whether TOU would be worth it. The ConEd folks I spoke to so far have advised that it's often not worth it, but I'm wondering what your experience has been so far?

Thanks!
Ben-

So I finally sat down to do some analysis of our bills since going TOU and... I still have no idea whether it was worth it. I think this TOU thing is still new for ConEd because our bills do show two different meter readings but there is *NO* indication anywhere on the bill of the peak vs. non-peak rates and charges. For example, for November of 2013, our "meter 1" usage was 182 kWh and our "meter 2" usage was 433 kWh. I'm assuming the higher number is off-peak because the solar is offsetting peak usage and we're scheduling higher power tasks for nights/weekends, but I'm not 100% sure of that. In the charges part of the bill it just takes the total usage (615 kWh) and multiplies that by the delivery charge ($.1074/kWh) and the supply charge ($.1433/kWh). So that's a net cost per kWh of about 25 cents (plus tax) per killowatt hour of usage for November.

Online the situation is even worse as it only shows net usage with no distinction between peak and off-peak usage. But we did get a mystery credit of almost $800 on our bill in December of last year, so maybe that's some calculation of TOU rates and credits?

I've got another e-mail into ConEd about it to see what's going on but I may end up having to call them and (hopefully) will get to speak to someone who knows what they are talking about. Either they forgot to switch me over to the new TOU billing or they're doing the math behind the scenes and not showing it on the bill nor online.

The only thing clear to me is that ConEd's bills and online information system are pretty weak. Will update the thread if I learn more.

Thanks,

-Chris

[snic]

Ok, I spoke with someone at ConEd here in NYC who (finally) seemed quite knowledgable about the time-of-use and net-meters, Jim from the Distributed Generation Group. He explained why TOU billing does not work out well for 99% of customers with solar panels. Why this information is not available on their website is another question, but he did mention they're in the process of doing a "large data project" on the topic, so hopefully that will result in improved information throughout the company. In any case here's the story...

As you probably know, ConEd's TOU billing splits the day into segments; Peak which is weekdays from 10am-10pm and Off-Peak which is weekends and 10pm-10am weekdays. The two segments are billed at different rates and, most importantly for us, the power generated in one segment is apparently NOT applied to the other segment. What that means is that all the power generated during weekdays is applied against your weekday usage, but not against your nighttime/weekend usage. So you likely end up with a surplus of Peak power and a deficit of Off-Peak power. That part makes sense, but where ConEd gets you is that they don't pay you for your surplus of Peak power at the Peak power rates. Instead they wait until the end of the year and then pay you for any surplus at that point based on what sounds like the lowest rate of the year. So in other words you pay high rates for any net-deficit you have, but you get paid low rates for any net-surplus you end up with.

So in my case, despite Jim's suggestion that I skip the TOU meter, I've gone ahead and requested the TOU+Net Meter, since the TOU billing is voluntary and I can cancel it at anytime (http://www.coned.com/customercentral...svoluntary.asp). While I believe him that the TOU billing will likely not benefit me given the current billing policy, having the TOU meter will allow me to measure my peak vs off-peak usage and will put me in a better position to choose TOU billing or not.

Hopefully this all makes sense, but let me know if you've got questions about it. Also let me know how things have sorked out in your situation. Thanks!

Thanks for this summary - it's very useful. I share your frustration that this information isn't posted anywhere on the Con-Ed website.

The part I bolded is intriguing. What this suggests to me is that Con-Ed is willing to pay retail rates for surplus energy generation if you have a TOU plan. Are you sure that's what will actually happen? If you don't have TOU and you generate a surplus in a year, they will buy it from you at wholesale rates ($0.05/kWh or something like that).

If Con-Ed really pays retail for surplus generated at peak times (even if it's the lowest retail rate of the year), that might change the equation considerably. If you can generate sizeable surpluses, then selling that power to Con-Ed at retail might go some distance towards the cost of power you use at night and on weekends.

I'm glad you're getting the TOU meter and trying the experiment - please be sure to report the results!

[Volusiano]

If your production cover near 100% of your demand, then it's a no-brainer that you don't want to use TOU plan.

But if your production is only a portion of your demand, TOU plan may still give you an advantage. For example, if 50% of your usage is during on peak hours (10am-10pm), and your solar production is (mostly during this on-peak time anyway) only 50% of your demand, then your solar production covers most of your higher-price on-peak energy cost and is used up without a surplus, and you get to pay the utility a lower price for your off peak usage.

[benneb]

Ok, I spoke with someone at ConEd here in NYC who (finally) seemed quite knowledgable about the time-of-use and net-meters, Jim from the Distributed Generation Group. He explained why TOU billing does not work out well for 99% of customers with solar panels. Why this information is not available on their website is another question, but he did mention they're in the process of doing a "large data project" on the topic, so hopefully that will result in improved information throughout the company. In any case here's the story...

As you probably know, ConEd's TOU billing splits the day into segments; Peak which is weekdays from 10am-10pm and Off-Peak which is weekends and 10pm-10am weekdays. The two segments are billed at different rates and, most importantly for us, the power generated in one segment is apparently NOT applied to the other segment. What that means is that all the power generated during weekdays is applied against your weekday usage, but not against your nighttime/weekend usage. So you likely end up with a surplus of Peak power and a deficit of Off-Peak power. That part makes sense, but where ConEd gets you is that they don't pay you for your surplus of Peak power at the Peak power rates. Instead they wait until the end of the year and then pay you for any surplus at that point based on what sounds like the lowest rate of the year. So in other words you pay high rates for any net-deficit you have, but you get paid low rates for any net-surplus you end up with.

So in my case, despite Jim's suggestion that I skip the TOU meter, I've gone ahead and requested the TOU+Net Meter, since the TOU billing is voluntary and I can cancel it at anytime (http://www.coned.com/customercentral...svoluntary.asp). While I believe him that the TOU billing will likely not benefit me given the current billing policy, having the TOU meter will allow me to measure my peak vs off-peak usage and will put me in a better position to choose TOU billing or not.

Hopefully this all makes sense, but let me know if you've got questions about it. Also let me know how things have sorked out in your situation. Thanks!

[MrBoylan]

Yes, all the rebates and credits definitely went into our upfront calculations, but thanks for checking! I'm curious to hear that leasing was a viable option for you as the leasing option my contractor, Greenlogic, presented wasn't even close to being competitive with the purchase / finance options they gave. Maybe the system size plays a factor there? In any case congratulations for already being net positive... That's quite amazing... I think my break even period is more like 7 years!

Well honestly I think Sungevity (our lease provider) may have underestimated the cost of doing business in NYC and we were one of their first customers so we benefited from that. Our up-front lease price was about $3K for a 20-year-lease (paid up front, no monthly payments). But we got a $1000 instant rebate for following a referral link (that has now been decreased to $500, which is still nice). So our net cost up front was around $2,000. Again, not a powerful system, but at that cost, it was easy to break even.

You can get a quote from Sungevity here: http://bit.ly/sun-power (well not you, since you already have a system, but lurkers). Full disclosure - that is our referral link so both the buyer and we would get a $500 sign-up bonus from using that link.

-CB

[MrBoylan]

Well we just got activated a couple weeks ago, but so far we're getting about 30 kWh/day... 521 kWh total so far...

Nice! Our best day was in June, at at nearly 10 kWH.

It's really too bad the off-peak time doesn't start earlier;7 or 8pm would really be ideal for us.

Ya, 10 PM is kinda ridiculous. I don't think we'll really see significant savings until next Summer if/when we go away for extended periods.

Anyway definitely let us know once you get that first bill. I'm very curious to see if ConEd actually pays the peak rate for peak generation or if it just gets 'bucketed' as they do in NJ. Also one ConEd rep told me they thought there was a 3 month 'lock-in' period for TOU... The website doesn't mention that though... Have you been told anything concrete?

This is what they told me: "Once on this rate, we would need a written request from you to return to your standard rate. There is no term nor penalty charge but you would be ineligible to re-apply for the time-of-use rate for eighteen months." so that doesn't sound like a 90-day lock-in.

Also, I think the difference between peak and off-peak charger is much slighter now (October-May) so we're only likely to see a significant savings for the August and September bills. Anyway, will let you know the details once I can see and crunch the numbers.

Regards,

-Chris

[benneb]

BTW, Ben, off-topic but do you know about all the NYC and NY State rebates?

Yes, all the rebates and credits definitely went into our upfront calculations, but thanks for checking! I'm curious to hear that leasing was a viable option for you as the leasing option my contractor, Greenlogic, presented wasn't even close to being competitive with the purchase / finance options they gave. Maybe the system size plays a factor there? In any case congratulations for already being net positive... That's quite amazing... I think my break even period is more like 7 years!

[benneb]

How much are you generating in a month?

Well we just got activated a couple weeks ago, but so far we're getting about 30 kWh/day... 521 kWh total so far... I'm definitely feeling very fortunate that we have a larger roof!

On the other hand, I'm not sure if we'll be as successful as you in shifting our usage to after 10pm... It's really too bad the off-peak time doesn't start earlier;7 or 8pm would really be ideal for us.

Anyway definitely let us know once you get that first bill. I'm very curious to see if ConEd actually pays the peak rate for peak generation or if it just gets 'bucketed' as they do in NJ. Also one ConEd rep told me they thought there was a 3 month 'lock-in' period for TOU... The website doesn't mention that though... Have you been told anything concrete?

Thanks!

[MrBoylan]

Hey CB, any updates?

I recently got a PV installation on my house here in NYC (although mine is larger at 7.194kW) and I'm currently debating whether TOU would be worth it. The ConEd folks I spoke to so far have advised that it's often not worth it, but I'm wondering what your experience has been so far?

Thanks!
Ben-

BTW, Ben, off-topic but do you know about all the NYC and NY State rebates? NY State offers a 25% tax credit for solar purchase *OR* solar lease (lease credit just went into effect in 2012). Federal government has a 30% tax credit on system cost to homeowner, and New York City offers a property tax abatement of 5% of the total system price per year for 4 years. That NYC property tax credit is great for leasers in particular as it is 5% of the system installation cost, which was around $10K for our system (even though we only paid about $3K for the lease). The system cost was the installation cost paid by Sungevity. I didn't even know about the property tax abatement until Sungevity told me about it and sent me all the paperwork.

We're already net positive for the system!

[MrBoylan]

Hey CB, any updates?

I recently got a PV installation on my house here in NYC (although mine is larger at 7.194kW) and I'm currently debating whether TOU would be worth it. The ConEd folks I spoke to so far have advised that it's often not worth it, but I'm wondering what your experience has been so far?

Thanks!
Ben-

Hi, Ben,

Lucky you for having a bigger roof. Mine was the biggest system we could get up there due to NYC fire codes. How much are you generating in a month? Our average over the summer was about 200 KwH/month, which worked out to around $50 in saved electricity costs thanks to the ridiculously high supply and delivery rates in NYC. This was on the fixed rate plan via ConEd and using an ESCO for electricity supply.

We did switch over to TOU but only toward the end of the summer (we waited for a while, and then there were some delays in getting the net TOU meter installed). So, although we did get the first TOU meter reading, we have not seen the first TOU bill yet.

It was a little tricky trying to avoid turning on the AC on some of the hotter days in August, but my wife didn't complain too much, and she has shifted a lot of activities (dishwasher, clothes washing/drying) to after 10:00 PM, before 10:00 AM or on weekends. As soon as we have a chance to go over our first bill or two, I will share the results. For a small system like mine, it might not end up being worthwhile (hard to offset the higher per-month fee associated with TOU), but I still think it will be marginally better going with Time-of-Use. For you it should be a little better unless you spend a lot of time in your home during peak hours during the week.

Regards,

-Chris

[benneb]

NYC Net + TOU Update?

Will share more when I know more (but it might be a while!).

Hey CB, any updates?

I recently got a PV installation on my house here in NYC (although mine is larger at 7.194kW) and I'm currently debating whether TOU would be worth it. The ConEd folks I spoke to so far have advised that it's often not worth it, but I'm wondering what your experience has been so far?

Thanks!
Ben-

[SunEagle]

Thanks for the tip. Not a bad price. In the kitchen, we currently have about 8 40-watt (or maybe 65-watt?) Incandescent spots in the high hats. These aren't on often, but when they are, they do suck up the power. Wondering how these LEDs would look in the hi-hats.

Gotta see if I can rustle up some PR contacts at Philips to maybe send me some "review samples" of their LED lights.

I am using 6 - 4 watt LED lamps in ceiling mounted cans in my kitchen. I also have 3 pendent lamps with 2 watt LED in each over the counter next to my sink. The total 30 watts of LED provides more than enough light for my kitchen. Since I originally had 8 - 4 foot and 2 - 2 foot fluorescent lamps for about 300 watts total I believe I did a great job of reducing my electrical use in a room that is always lit up.

[Lomag]

If you read this whole thread and then stand back and look at big picture, then the comments about timing activities to avoid the higher tariff periods of a day perfectly describe the intended result of TOU metering. That intent is to reduce demand on the utility during high consumer demand periods.

I'm in an area where TOU metering is unavailable. I work with a kWh bank similar to that described for NJ. Through out the year (May to April) I put in and take out of the bank. This is KWh$ per kWh$ with a value that includes all of the taxes, supply charges and everything else added on except the customer supply charge simply because I'm not buying. I'm happy with that.

However at the end of the year (April 30) the utility buys my excess and the bank account is empty going into May. The purchase price is only the Standard Offer Service and is about 1/2 the kWh cost because all the rest of the add-ons are not included.

March and April are very big production months here. My heat is mostly off and we get a lot of sun. So I put a lot of kWh into the bank during March and April only to be purchased by the utility at half price. But, even with that, going solar was the one of the better moves I've made.

Check with your utility, you should be able to change your anniversary or "true-up" period on emptying your bank one time only. Our system was installed in July and I called right away to change the anniversary period to March, specifically March 7th, when the bill for February is cut. So the bank can fill up during March/April/May to be used up during the peak summer months. Then re-filled during Sept/Oct/Nov to be used during the winter months.

[inetdog]

In the kitchen, we currently have about 8 40-watt (or maybe 65-watt?) Incandescent spots in the high hats. These aren't on often, but when they are, they do suck up the power. Wondering how these LEDs would look in the hi-hats.

I have used them in can type track fixtures which were designed for either Type A bulbs or reflector type and they look very good. Much better visually than even a reflector type CFL but they do give a somewhat broader light pattern. I have not used them in a deep-recess fixture designed only for reflector type bulbs, but depending on how you adjust the socket position inside the fixture they might do well. Probably not great for a fixture on a high (e.g. 2-story) ceiling unless you want the more diffuse light.

[DanS26]

Chris,

Lots of good suggestions so far. My experience is "do not guess" find out for sure based on your family's usage pattern. How do you do that? Use a system like the TED. You can set the system up for TOU but still use the regular rates from utility. Then compare for a few months. It will be obvious.

Now if your wife is like my wife she will not be tied to a timetable when she wants to use laundry. Or when she wants to bake a cake in the electric oven. TOU is putting your schedule subservient to the the utility schedule. Most people do not like that.

When Mama is unhappy nobody is happy and vice verse of course.