First month Solar Panels results

Congrats,

It's pretty exciting to see that it all does work.

As a caveat however,,, (and while I whole heartedly encourage PV,, in fact make part of a living with it) it is not "free power". In current dollars is is roughly twice as expensive per kwh as grid power.

As we say in the business, your cheapest RE dollar is conservation. For every dollar spent on conservation, you will save roughly ten in PV costs.

Icarus

 

Hey Hill that's great. So your new power meter should be reading , if a 6 digit meter, 999920kWh. At some point, and it's happened to me, the meter reader will enter the amount shown, and somebody will not think and let's say we use your current meter reading, charge you for 999920 kWh of usage!!! When I saw my $36,000.00 dollar power bill one day, I just busted out laughing!!!! When I called GWP, I wish I could have had a videophone connection because if the look on her face reflected the tone in her voice when she figured out the goof it would have been priceless!!!!!

 

Even ignoring all of the collateral costs, comparing the cost to the consumer depends on an estimate of the lifespan of the PV system and an estimate of electricity costs during that time.

I'm assuming that gas and electricity are both going to get pretty expensive, so investing in solar/geothermal seems like a pretty sound long-term purchase.

 

Hill,

Also planning a oversized PV for the future EV.
We have figured 150 Kwh/month (4 miles/Kwh @ 600 miles / month).

So if your 8o Kwh January "surplus" is located in Southern California, then looks like your annual surplus should easily cover your future EV.

But if your January "surplus" is located in the Flathead Valley, then you
have way overbuilt and I would recommend getting a fleet of EVs or an outdoor pool.

Good Job!!!

 

Hill,

I am not quite sure what you are are asking. If you just take the "retail cost per kwh" from grid (~$.10-.15) as opposed to the cost of a kwh fro PV solar, amortized over the life time of the hardware,,, in current dollars, the estimated cost comes in somewhere in the neighborhood of ~$.20/kwh.

IF, and that is a big IF, we were calculating the entire cost of grid power as you suggest, taking into account, C02 emissions, acid rain, nuke mining/waste management/ decommissioning costs etc. then PV solar is a winner hands down. My argument has always been that we have never paid the real and true costs for our energy choices,,, and we should.

As for my comment on conservation being more cost effective than PV solar. I know we have had this conversation on this forum before. My point is while it may make us feel good to put PV solar on our houses, if we do this before we do every conceivable conservation step,, we are in essence wasting our money.

For a simple example,,, a 15 watt CFL puts out the light equivalent of ~60 watts. To buy that 45 watts of PV would cost your roughly $8-10/watt,, or say for the sake of round numbers $400. The cost differential between the CFL and the conventional bulb might be say $1. (Not to mention the life span of the CFL, probably makes it's life cycle purchase cost LESS than a conventional bulb) (And please don't give me all the negative arguments about mercury and dangerous waste of CFLs,, proper recycling is in place almost every where. Also don't give me the line about the quality of light, from CFLs, as there ar hundreds of different styles, shapes and colors of CFls. Those that don't like them have never look real hard to find good ones! Products)

Now I admit you can get into all kinds of creative accounting, for the live cycle cost of the cfl and the live cycle cost of the 45 watts of PV, but the simple numbers speak for themselves.

The same can be said for any number of other household/commercial and industrial applications. A new fridge will use ~1/3 the energy of one that is 15 years old for example, ground source heat pumps, heat pumps that use waste heat to heat domestic hot water,, and so on are ALL provide much greater energy savings relative to their cost compared to adding a similar amount of PV solar.

I have always understood that solar,, especially PV solar is "Sexy" and that it gives people something to point to to show that they "get it" and that there is considerable value in that. It allows the acceptance of the technology to advance but I have also contended that insulating your attic to reduce heating or A/C cost while it may not be "Sexy", it is a better use of resources.

As I have always advised my clients, after you have done all the conservation you (and specialist experts) can think of,, then consider PV solar. (I once had a client who wanted to install a big PV solar system, and he wanted to use some of it to heat his hot water,,, electrically. When I explained to him that it would cost ~1/4 as much to heat the hot water directly from solar rather than use the PV,, it was an eye opening experience for him).

So,, as I suggested in my first post,,,Congratulations on you system, and hopefully a side benefit will be that it will encourage your neighbors to realize that they too can (and should) be doing something (more?) to reduce our conventional energy consumption.

Icarus

 

Wow! I barely break even in June with my 2.8 KW array. What have you got, 8KW? Maybe you should negotiate with your neighbors to sell some of your extra. Or start an aluminum plant...

Sounds like you didn't get a time-of-use meter. In my area in northern California the power company, PG&E, offers an optional rate schedule that bases the rate according to time of day and year. It's something like $0.35/KWH peak time (9-6?) and $0.08/KWH off-peak. November through April is all off-peak. The real advantage for a system like yours is that you get credit during the day at the high rate, and then spend it at night at the low rate. The disadvantage is that you have to think about what the rate is all the time. Things like washing clothes or running the dishwasher cost 4 times as much during the day as at night. And air conditioning might break the deal. Anyway, it's definitely worth trying to figure out the balance.

 

What is the assumed lifetime of the hardware? (The expensive panels anyway.)

What percentages of the install cost are the supplemental power handling/grid connection hardware and the overall installation expense, respectively?

I'm trying to get a feel for the cost of doing any installation vs. installing an incrementally larger one.

Does the 20 cents/kwh figure include incentives/rebates or is that the full installation cost?

 

Shawn,

I build small off grid systems, so I can only speak anecdotally, but I am dialed into the industry through a number of channel.

The warranted of most name brand panels is 20-25 years. In the real world, life expectancy is likely to be longer. Grid tie inverter warrantees run ~10+ years.

If properly done there is no reason to think that most systems should be trouble free for 20 years. There is little to go wrong with the wiring system that should need care in that time frame,,, aside from possible corrosion of connectors depending on climate and installation.

I'm not sure how you figure the "retail" cost of PV kwh, with respect to rebates etc. The number varies considerably with the utility as well as the state and local government incentives. The $.20/kwh is a number that seems to be a consensus in the PV field,,,, I cannot attest to it's complete veracity. That number will also change dramatically with location and climate. A sunny, cool location at lower latitude, (say New Mexico,, at elevation) would, on balance produce more PV than a similar latitude in desert California due to lower panel temps given equal sun over the year.

Similarly, an array in Seattle will produce way less on an annual basis than one in Moses Lake WA just because of the average insolation over the year.

Panel costs,,, (retail) today are running $4-5 per watt. Inverter costs run somewhere in the $1/watt range, so added together makes hardware costs ~$5-6/watt. Obviously labor is quite site specific, although as always, the more the merrier. Wiring a 10kw array isn't 10 times as much as a 1kw system.

A couple of things to keep in consideration going forward. The first is in this current economic situation, the costs seem to be going down,,, largely (IMHO) due to decreased demand for large scale systems leading to an over capacity of panel production. Also the local retail level installers are hurting and ergo might be willing to work for less.

The second issue is the effect on prices/demand short and long term due to both the recent "stimulus package" as well as some of the energy reforms coming forward in the budget. How these will effect prices in the short term are sort of any ones guess. There is the argument that prices have never (in real dollar for value) been lower and now is the time to jump. The second argument is that with additional incentives the prices could come down still further. (net/net) The countervail to that is that could push up demand such that either labor, or hardware (or both!) costs could rise, thereby offsetting any savings.

One new product on the market that may have potential to allow small scale grid tie systems to be installed by more people is the new "Enphase" micro inverter. Essentially these are small, UL listed grid tie inverters that can be installed one at a time one for each panel, such that it would allow one to build a system one panel set at a time, without the huge up front expense. One does lose a certain economy of scale, but it would allow someone to get started for under $1000 with a grid tied system.Enphase Micro-inverter Grid-Tie Systems (This is one of the only "new" things to come along in a while that is real, and ready, and not hype. It isn't really any cheaper,, but just a different way of doing it!)

For those that have an interest,,, I suggest (again) that you visit the following forum :Grid Connected Solar Electric & Wind - Solar Electric Discussion Forum by Northern Arizona Wind & Sun

Populated by some very smart, very tuned in folks who have forgotten more about RE/PV than most of us will ever know.

Icarus

 

icarus,

The key to me is requirements for utilitiies to get increasing percentages of their power from renewables, and give them credit for grid tied systems. If somebody produces a few thousand kWh/year (even if they consume all of it) give the utility credit (or some credit) for that production. Doing this should enourage utilities to partially subsidize residential PV, wind, etc. because it would reduce investment costs that they would otherwise be required to make.

If we get the homeowner's initial costs down there will be a mass move toward this in new construction.

 

I've maintained that line for years now, but extended to our overall infrastructure. Politicians get a lot of airtime when they open a fancy-schmancy community center or skating rink, but nobody gives one s*** about waste water or potable water treatment systems

How about the fact that a lot of the potable water network is dangerously old, exceeding its designed lifespan, and already leaking? What folks fail to realize is that a lot of tasty organics get introduced when the pipes rot and start leaking

A similar caveat applies to our electrical distribution network. Unless there is a major failure - resulting in politicians doing a lot of tongue wagging in front of the cameras - nothing is ever upgraded. I don't even like thinking about the inefficiencies that are part of our "modern" electrical grid system

Actually, a lot of casual onlookers assume that they can do things like that. For a long time our electricity has been so cheap, that we could use it to directly heat potable water and even our homes

In Manitoba, the power is still cheap enough that for a home my size, an electric furnace would be around 10% cheaper to heat than a gas furnace

 

"a lot of casual onlookers assume that they can do things like that. For a long time our electricity has been so cheap, that we could use it to directly heat potable water and even our homes

In Manitoba, the power is still cheap enough that for a home my size, an electric furnace would be around 10% cheaper to heat than a gas furnace"

I have no objection to resistance electric heat provided A: it comes from a never ending hydro source that has no other available use on it's grid. In other words almost never. If for example live off grid, you have on site a small scale hydro system, and you have enough excess capacity that you can heat your space and your water,,, well good on you.

My suspicion is that Manitoba Hydro doesn't get all it's energy from hydro, no does it have excess capacity on it's grid.

Icarus

 

According to the left wing NDP government, around 96% of total power generated is from hydro sources, and 50% of total power generated is exported

Climate and Green Initiatives | Science, Technology, Energy and Mines | Province of Manitoba

Keep in mind that these hydro projects are very huge, not small scall low head projects. I find it rather disingenuous that the NDP's are thumping the Green thing withouth pointing out that massive flooded areas can also be a substantial source of GHG emissions

 

hill,

I don't know how they are doing their estimates, but when you cut electrical usage you back out fossil fuels first. The nuke, hydro, wind should be running at normal capacity with the swing coming from natural gas, first typically. Coal plants are a bit harder to back off on if I understand correctly.

Operating cost-wise natural gas is the most expensive of the choices above, so it is the one that you want to back out first. So my guess is that the CO2 saving formula would be based on natural gas.

 

You absolutely do *not* want to "throttle" coal plants. The nature of coal firing, the steam and recovery system, dictate steady-state operations.

At the very least, you will have much increased emissions from attempting to "throttle" a coal fired plant. You will also have much increased thermal stresses, possibly leading to early failure

 

Jayman, can you elorate on this a bit? Is the reason for the coal fired lag times a result of the fact that you have a large mass of buring coal versus a hot but quickly extinguished flame in a gas fired plant? Is this why peaking plants are typicall NG fired?