Are you a net producer or consumer of electricity?

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leafetarian said:
Another thing they tell me is that my PG&E bill is too low to make solar financially viable. My usage is between 320 kwh - 450 kwh per month (not more than 500 kwh). Is that also a problem?
I am OK with longer solar payoff if somebody can work with my roof shading issues.

Can you recommend any solar companies that will give me solar report?

Sorry, different state. Up here since I was doing it myself I hired someone to do the solar path analysis. Even with my 28% annual shading the combination of federal rebate, sales tax exemption, state 15.4 cents per KWH production credit and significant savings doing it myself it still made financial sense.

You use enough electricity that you would still need a significant sized system to generate a surplus. I guess one issue is that the cost of the electricity you use is cheaper than someone that is using a ton more.

Do have any clear east/west exposure? This ends up affecting your production something like 15% which shouldn't be enough for it to not be worthwhile.
 
leafetarian said:
Can you recommend any solar companies that will give me solar report?

Funny timing. Check out this thread: http://www.mynissanleaf.com/viewtopic.php?f=45&t=8272&p=208221#p208219" onclick="window.open(this.href);return false;
 
I am a net consumer, used to be 66% self sufficient from our 4 kW solar, but now with the leaf down
to 50%... Seattle is not the sunniest place, but the rainy cold summers have their advantages (think battery life) too :D
 
I am a net producer... at least so far this year. We'll see how the electrons stack up as the days grow shorter and the angle lower. In the meantime, I am happy to put my zero-emissions surplus into the grid to help charge your Leafs.

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Have a 3.92 KW system in Hawaii, which of course has great solar insolation and is producing a little over the rated 6,600 KwH annually. Until we started driving/charging (L2) at home the LEAF, we were net producers, utilizing about 5,000 KwH annually for household needs. After a couple months with the LEAF, seeing about 4.00 Wall to Wheels KwH efficiency, I'm estimating about 2,800 KwH annual consumption for charging - which will clearly require an upgrade of our net metered PV system to zero out.
Hawaii has the highest residential electrical costs in the nation, currently running about $ 0.36 per KwH for a typical user, with a 7% inflation curve over last 5 years....which makes using solar more critical to EV economics than maybe so in other places with more reasonable electricity rates. Our power company, HECO, uses a running cash credit reconciliation process, but at the end of a 12 month period, any cash credits go back to them and you are zeroed out for the next 12 months. Their feed in tariff program, wherein one can sell power to the grid at a long term fixed rate, is generally considered unfavorable to residential users because it locks in about $ .21 per KwH provided for a long period. HECO also has a TOU program specifically for EV users, but it is indexed so that you pay 0.06 less than the going rate for off-peak charging, and if you happen to charge during peak hours, you pay $ 0.02 more than the going rate. And the user has to pay for the separate meter dedicated to the EV charging circuit - so I'm not sure that is such a great deal.
As I have TED to monitor both the PV system generation and household consumption, with a 3rd independent monitor for the EV charging circuit, I should be able to nail down the EV consumption data pretty well with a few more months experience with the LEAF.
One question I have, that I will probably post in the battery/efficiency sub-forum, is whether I can expect the efficiency of the battery to degrade over the years of operation - or just the battery capacity. Since our short commute doesn't make the expected degradation in battery capacity (e.g. range on a single charge) a major issue, what about efficiency. Can I expect the wall-to-wheels efficiency to degrade with time, even at a lesser rate? Some say no, but it seems that as a battery's capacity to carry power gets reduced over time, it's ability to receive that power and to convert it to mechanical power would be less than when it is brand new. Another factor to consider when designing the solar system upgrade...including the 0.5% annual de-rate in PV production, electrical rate inflation, increase in household consumption with two growing kids...and the like. :D
 
Phoenix said:
leafetarian said:
Question:
For the net producers, does your utility send you a check? Specifically, I want to know what it might take to make PG&E in CA to pay net solar producers? It sounds no brainer to me as they have no problem paying polluting coal / gas power plants and nuclear power plants. Why not pay families producing excess solar electricity?

I was told by PG&E that they pay only 4 cents a kWh and you have to be a net producer. Cost-wise because of time of use, my bills showed a credit of $300, but since my kilowatt usage was a positive instead of a negative figure, I don't get a check for $300. Next year, EVs can charge free at my house if it looks like I have a monetary credit. (BTW, we should start such a network of solar PV in the SF Bay Area. Perhaps to especially welcome apartment/condo dwellers who need charging.)

From a policy standpoint, PG&E does NOT encourage energy efficiency which its Pacific Energy Center espouses.

Phoenix, are you on a net metering rate schedule? I'm told that the law recently changed and now utilities must write you a check if you have a credit at the end of the year (or whenever your 12-month true-up cycle ends). You should now get a check for $300.

We just put a 4.94 Kw system on our roof and we are waiting for PG&E to swap the meter so we can turn the system on. It's killing me seeing the panels up there and not being allowed to use them.
 
DevPrius: Not what PG&E's solar division (based in San Jose) told me. Yes, I am on net metering. If you are in PG&E's service area, you only get paid at the annual true-up if your net kwh usage is a negative number. Yes, the law changed so you now can get reimbursement (set at 4 cents per kwh) when you are a net producer. But this is not to say you get reimbursed for the net monetary credits shown on your monthly statements.
 
Phoenix said:
DevPrius: Not what PG&E's solar division (based in San Jose) told me. Yes, I am on net metering. If you are in PG&E's service area, you only get paid at the annual true-up if your net kwh usage is a negative number. Yes, the law changed so you now can get reimbursement (set at 4 cents per kwh) when you are a net producer. But this is not to say you get reimbursed for the net monetary credits shown on your monthly statements.

PG&E has done a pretty poor job on their website explaining how net metering and credits is supposed to work. I finally found the section that says that if you produce a surplus of electricity, they'll pay you for it, but at wholesale rates. In another part, they talk about how you can carry the credit forward indefinitely now, but don't go into detail if that's a credit at retail rates, or just raw Kwh. And I haven't found an explanation of how the credit works when you are a net-consumer of power, but have earned a money credit due to the fact that you produced a lot of electricity during peak times but used little of it, and instead shifted usage to off-peak times where the electricity is cheaper. Will they write me a check for the surplus money? Or is it another credit that gets carried forward indefinitely?
 
devprius said:
<<snip>> Will they write me a check for the surplus money? Or is it another credit that gets carried forward indefinitely?

Not for me--no check for the surplus money and I am on E-7. Nor does my credit get carried forward. It gets zero-ed out at the annual true-up. You may be on a different solar rate E6? If this is wrong, I am all ears.
 
Phoenix said:
devprius said:
<<snip>> Will they write me a check for the surplus money? Or is it another credit that gets carried forward indefinitely?

Not for me--no check for the surplus money and I am on E-7. Nor does my credit get carried forward. It gets zero-ed out at the annual true-up. You may be on a different solar rate E6? If this is wrong, I am all ears.

We'll be on E6-TOU, if PG&E ever gets around to swapping the meter. 2 weeks and counting. They have 30 business days, or 6
calendar weeks, to do the swap and let us turn on the system for real. So in theory we have another 4 weeks to wait.

PG&E's website is contradictory with regards to NEM surplus generation:
From: http://www.pge.com/myhome/saveenergymoney/solarenergy/nembilling/" onclick="window.open(this.href);return false;
it says:

6) Any remaining charges must be paid and any excess credits are typically zeroed out. However, once the AB 920 program goes into effect in 2011, if the customer is a "net generator," i.e., they provide more electricity (kWh) to PG&E’s grid than they receive from the grid over the 12 month annual billing cycle they may:

* a) Receive compensation for the surplus generation;
* b) Receive credit for the surplus generation and apply it toward subsequent kilowatt hours (kWh) supplied by PG&E, or;
* c) Not participate in either option.

As provided in AB 920, the details regarding these options will be developed and finalized in the coming months. PG&E will provide updated information as it becomes available.

But another FAQ at http://www.pge.com/myhome/saveenergymoney/solarenergy/afterinstalling/ab920/" onclick="window.open(this.href);return false;
doesn't mention anything about carrying the surplus generation forward. Looks like they were allowed to drop the provision for carrying the credit forward.
 
kovalb said:
The next time our hot water heater goes out I am going to strongly consider replacing it with a heat pump type - they are very efficient, especially when the garage they are in has an ambient temperature almost equal to the hot water.
Our water heater was due for replacement and I installed a heat-pump water heater on Saturday. As a result, I think we just changed from being net consumers of electricity to net producers. I'm thinking we reduced our electricity consumption by over 5 MWh/year with this change since our old heater was in bad shape and likely was leaking a lot of heat into the environment.

Assuming the compressor unit survives, this unit should pay for itself within two years given the tax credits and since we are running it in heat-pump-only mode. Unfortunately, that may be a big assumption. I see quite a few stories about failed compressors within the first year. But it's difficult to guess at a failure rate based on those types of anecdotes, particularly since some of those units may have been improperly installed or placed in inappropriate locations. It comes with a 10-year warranty on parts with one year including labor. We'll see how things go.
 
Can you share with us what heat pump you installed, its specifications and approximate price? Do you have solar thermal water heating in combination with the heat pump? Thanks.
 
Phoenix said:
Can you share with us what heat pump you installed, its specifications and approximate price? Do you have solar thermal water heating in combination with the heat pump? Thanks.
Sure.

GE Model #GEH50DNSRSA (It's the discontinued version of their GeoSpring HPWHs. It holds 50 gallons of water.). Price for the floor model was $938 plus tax = $984.90. The new one retails for $1199.00, but I'm sure you can get a discount on that. I think there may still be a 30% federal tax credit on this, but I am not sure. Warranty is 10 years parts and 1 year labor.

I have looked carefully at solar water heating but it was coming in over $5000 if I installed it myself and twice that with an installer. Warranty was only 3 years for a self-install versus 10 with the installer. Solar water was more Rube Goldberg than a HPWH, although I imagine I would have additional maintenance on either one versus traditional.

In the past I had a Seisco 14 kW electric on-demand water heater. It suited us fine and saved about 60% over the tank we had previously. Unfortunately after about 18 months an O-ring cracked and the unit was destroyed when the water hit the control circuitry. There was a long lead time for a replacement, so I ended up with a tank again.

No natural gas here. We have propane, but it is expensive and I would be happy to get rid of it completely. My wife like to cook with it, so it survives...
 
After numerous changes, additions and subtractions, I should be a net producer even with the LEAF, I'll know for sure after the winter. I've found it's very important to watch both parts of the equation, use and production. The best solar installers tell you right up front the biggest bang for the buck is efficiency. Insulation, efficient appliances, lights. I've been doing all of the above. I have two sets of solar panels, both 4.73kw, for a total of 9.46. I added the second solar panel set as I was converting to solar hot water and geothermal HVAC from gas. I'm still careful to combine trips with the LEAF and to conserve whenever I can to try to stay on the positive side. I look at this as a safer investment than stocks for retirement, I know for sure I'm going to get a return on this investment.

I'm impressed with the number of LEAF owners who also have solar. It makes all the sense in the world, and it's good to have to wonder whether the LEAF makes the solar panels pay for themselves quicker or the solar panels help the LEAF pay off quicker.
 
Goalnetpositive said:
it's good to have to wonder whether the LEAF makes the solar panels pay for themselves quicker or the solar panels help the LEAF pay off quicker.

I'd strongly argue neither. The break even point on the LEAF is the same whether you have solar panels or not. The break even point on the solar panels is the same whether you have a LEAF or not. I say that with the caveat of tiered rate structures and if you are producing more power than your utility will buy back these would complicate the issue.
 
RegGuheert said:
We are still net consumers. While we almost never run our air conditioner, we heat with a heat pump in the wintertime and that consumes more than the excess we produce during other months.
There have been several changes around here since 2012 when I wrote that, so I thought I would take a look at where we stand right now. While I have access to detailed data on the production of my PV array, I have very spotty data from the energy meter attached to the electrical grid. That is because the utility only reports our reading on the bill if it is above the high-water mark for the past 12-month period. Additionally, I don't make meter readings myself. As such, the only readings I have from 2015 were on February 3, March 3 and April 3. So I will try to calculate what portion of my annual consumption was provided by PV on those three dates this year.

February 3:

Feb 3, 2015 meter reading: 12,656 kWh
Feb 3, 2016 meter reading: 14,225 kWh
Grid consumption during past 12 months: 1569 kWh

PV production from Feb 2015 through Jan 2016: 18,361 kWh

Total electricity consumption: 19,930 kWh

Fraction provided by PV: 92%

I do expect this fraction to increase over the next six months since my heat-pump water heater lost its charge and was wasting massive amounts of electricity until June 15, 2015. For 1/3 year, I estimate that it could have used an extra 1.5 MWh over normal consumption. In other words, I am hopeful that I am converging on matching production and consumption. Time will tell.

Last year we consumed a total of 3118 kWh during February. Hopefully we will come in under that amount this month.
 
My electricity production from my 2170 watt solar array was 120% of my use last year. Even counting charging away from home I would guess that I was a net producer.

For just my home system, I have a carryover credit of more than 900 kWh banked for use with my Model S, which I expect to use more electricity per mile, and be used for more miles, than my LEAF. Counting charging away from home, I would expect the Model S to tip me into being a net consumer. Those thousand mile trips will add a lot of miles over what the LEAF did; I burned gas in my ICEV for those miles in previous years.

I've already sold my ICEV, although I haven't delivered it yet. Once it is gone my last ICE device will be my little 16 inch chainsaw, which goes through about 0.6 gallons of gas each winter during tree thinning season.
 
Cool thread, great to see a number of net producers!

We are currently a net consumer (PV panels cover about 30% of our home plus transportation.

In a few months we will have completed our new house.
Our new house is designed to produce, on an annual basis, all the electricity our house and cars use.

Metal roof just went up last week. Garage with two NEMA 14-50s and a backup/visitor 240V, 20Amp are all set in the garage.
 
RegGuheert said:
February 3:

Feb 3, 2015 meter reading: 12,656 kWh
Feb 3, 2016 meter reading: 14,225 kWh
Grid consumption during past 12 months: 1569 kWh

PV production from Feb 2015 through Jan 2016: 18,361 kWh

Total electricity consumption: 19,930 kWh

Fraction provided by PV: 92%
March 3:

Mar 3, 2015 meter reading: 14,413 kWh
Mar 3, 2016 meter reading: 14,763 kWh
Net grid consumption during past 12 months: 350 kWh

PV production from Mar 2015 through Feb 2016: 18,192 kWh

Total electricity consumption: 18,542 kWh

Fraction provided by PV: 98%

Good news! I'm approaching 100% PV coverage for all electricity usage (given almost-free storage through net metering). If we get some more sunny days this month, I may cross over on April 3.
 
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