So many of the posters and proponents of alternate energy solutions seek to get off the grid which I am coming to think is a bad approach.

By connecting to a complex and smart grid could we not exchange our energy better? we generate when the wind blows or sun shines and consume when we don't. We use the grid to stabilize and offset consumtion. On hot and clear summer days the grid gets lots of added power from our little home solar systems and the hydro and steam powered generators can throttle down or in the case of some hydro, pump the water back up the hill with the surplus.
I would think the socially responsible approach is to increase the grid ties rather than get off.
The more producers makes the grid more reliable, but of course more dangerous too, as the power can come from many more sources.

Mikesh:
Of all the solar installs in the Twp I work in, they are all grid tied. I have not seen any that are stand-alone.

There is one wind turbine job, 4KW that is 'designed' with storage batteries, and no grid tie as of yet, and that is not in the job scope.

The thread that is titled 'Big' is a POCO project, and it is grid only, and classified as a generation installation.

John,

I some rural areas around here I have seen out buildings ( garages, barns) that are not on the grid at all. They are stand alone systems. Most of the time, the PV systems are connected to the grid.

Part of the issue is, are we talking about Transmission or Distribution grid ties?

Where are the most losses? How do we deal with large area variations when the sun goes behind clouds or the storm front blows through? How do you deal with islanding? What about remote generation tied into a remote spur that requires upsizing the spur? One of the issues with using a variable output power source is maintaining grid stability. Ramping up and down hydro is not a 5 second operation. Gas Turbines are 15 minutes to bring online. Coal and biomass may take 6-12 hours for large power shifts.

Grid stability may initially go down before it comes back up. Unfortunatly I don't not know of any quick responding, large capacity power absorbtion / storage / regeneration technologies that are commercially available and economically viable yet. Flywheel systems are beginning to address this but they are not wide spread yet.

How many substations are setup to take power From the distribution system and push it back into the transmission lines to be used somewhere else?

I'm just doing my job of stirring the pot.

You bring up some good points Larry. Within my Twp we have modest resi systems dumping into the 120/240 secondaries, comm jobs, dumping 480, 3 phase into the secondaries of the respective pad mount xfrs, and I guess in theory...back to the primary (13.2/25 KV) distribution. One could also guess that it could be 'used' at a neighboring non-solar occupancy, or find it's way back to a sub station. That I will leave to those who have more theoretical brain cells then I.

The instability of the generation source as to weather related, time of day, season, maintenance, etc. are things that I have thought about, and debated with a few solar installers. No concensus was made, but opinions are plentiful.

One upcoming job is 4.26 MW in an industrial area. My opinion on that...the refrig whse will use a quantity, and some of the adjacent facilities will probably consume the balance.

Anybody else have opinions???

If the ads are any clue, this mystical new "smart grid" technology will solve everything, although I'm not exactly clear on what said technology is and why it's so important if grid-tie systems worked just fine before. Sounds to me like just another buzz word for the naturally occurring evolution of generation, distribution and metering technology.

In theory, it sounds best to me to keep everyone tied together. While solar isn't going to keep the lights on at night, it can at least help with the peak usage during the daytime. Until cheap storage comes around, we'll probably be dealing with large base load generating stations for a very long time... At least until we have macro power grids of superconductive materials, so we can pull solar from the other side of the world :P

I think there will be some "fuel charge" savings to be had in these distributed energy systems but all of the fixed charges will end up being higher. You still need the capacity to supply the whole grid in a blizzard so the utility still needs the same plant. Having it sit idle may actually be more expensive than running it, from a maintenance standpoint, and you need the crew in there ready to pull the trigger at a moment's notice. In subtropical environments, big storms can come up with a moment's notice.
It is certainly more convenient for the homeowner to shift the management of their excess power over to the utility instead of storing it on site but there ain't no free lunch.

Perhaps smaller generators, such as gas fuel cells like the "Bloom Box" will find their way into substations, to supplement what is already available in the neighborhood. That could take over for the solar/wind/etc. when it's not sunny or windy.

I'm not saying that centralized power plants should or will go away soon, but there are smaller-scale technologies that people will want to cash in on. There will always be a need for base-load generating, and I'm sure there are plenty of smart people who can figure out demand models for traditional generating stations and contingencies for when the weather doesn't pan out. It's not a change that is going to happen overnight. These small-scale things are probably not going to do serious damage to big power any time soon. It may be that, as time goes on and better technologies become available, the supplemental power is used to phase out dirtier tech like coal.

Ironically, the solar highway project I posted about a while ago had its first day of grid-tied generation when all of the panels were covered in snow. They even produce some power (around 500W) at night, although nowhere near the designed capacity of 104kW.

Wonder where the 500w comes from at night?

Is it from 50,000w of HIDs ringing the plant to show off how we are saving you money?

Streetlights! Here, just a cotton-pickin' minute....

No lighting was added... The panels are located in an island in the middle of the I-5/I-205 interchange, so there are some lights around. One of the claims/reasons given for doing the project, is to offset the power consumed by the highway lighting. This was a small-scale test project for an even bigger project up the highway which is currently stalled not because of the cost or perceived benefit, but because the rich people across the river claim it will be too ugly to look at on the hillside.

Here's the monitoring data, with some very basic project info: http://live.deckmonitoring.com/?id=solarhighway

Greg:
Maybe Alan has a point? The POCO pole mounted solar panels here (NJ) some are mounted under the streetlights.

As most streetlights were changed out to induction units at 150 watts, I wonder if the panel underneath puts out the rated 200 watts at nite?

Kinda like a perpetual motion thing??? LOL

Street luminaires ? well it can be done but how effect it will be due the type of bulb colour that may affect so I haven't try the test yet.

But if you use the common run of mill HPS and MH and see the diffrence between the two I don't think it will make a wide margan on diffrence on luminaire source.

Merci.
Marc

Look on it as 'regenerative braking for photons' - It was all headed for the Martians anyways!

I can see the attraction of your own battery storage, because you are not then at the mercy of future POCO tariff differentials between your production and use suddenly making a mockery of your original investment calculations. Or at the mercy of power cuts. On the other hand, the grid ain't going to wear out like a set of storage cells and would be equal to a heck of a lot of $$$ worth of them. One thing bothers me. If you are generating at 240v, your power is not going to go economically more than a few miles, unless it backfeeds the transmission transformers to higher voltages. Is that possible?

Until there is a very significant amount of grid tie PV it won't really have to travel very far. Usually your next door neighbor will use all of your excess unless he is making more than he can use.

Greg I have the feeling that like mobile phones, hula hoops and broadband, PV will suddenly take off to the point where we all have them and can't imagine how we managed before - probably triggered by a really cheap cell becoming available.

Alan:
The project titled 'Big' is a solar farm (POCO owned) that has zero consumption at the site, and is considered a 'generation plant'.

Panels, to combiner boxes, to inverters (output 480 volt) to feed padmount transformers (480 to 13.2KV)

I can't say how 'far' it's going to travel....those pesky little electrons are tough to follow & look alike! LOL

Well, I just read an IAEI article that lets the cat out of the bag: the motive behind the 'smart grid' push is purely political, an experiment in social science to regulate / modify behavior.

What behavior is encouraged? That's harder to fathom ... what's clear is that having the information available, as well as variable utility rates, will allow "someone" to influence your choices by opening your pocketbook.

We could very well end up with something like airline fares today, where no two people pay the same rate. This will also insert another agency into the mix the next time you build a hot tub or even replace a water heater.

Remember: The abuse of power is always in the right hands.

In reference to the OP and I apologize if I duplicate any info. It has been a very busy summeer and week and I am too tied to read trough all the posts. Just like to be a sucessful business, its location, location, location. The industry as a whole is leaning more to grid tie and less to off grid. Its world wide and the US is lagging behind the rest of the industrail world.

Due to the high cost of construction of a complete system, its a hard pill to swallow to pay your electric bill up front per say and if the system will not pay for its self then, why even bother? I have done several off grid systems here in Alaska. They came with a pretty heafty price tag giving their locations that are only used in the sunmmer. It those same locations that makes it a viable solution especially since the higher fuel costs and the cost to get fuel to these sites. On the other side of the coin a grid tie system is not viable since most larger comuunities are on hydro and the sun is not the best source in the winter months up here. At the remote sites, its like $3.00 per kilowatt (not a typo) com paired to $0.08 to $0.65 cents pending on where you live.

With a grid-tie system, the POCO's may be required to buy your surplus power but they are the ones who set the rates and the requirements. They will charge you retail for their power that you use but will only pay you wholesale for what you sell them. They basically call the shots on theit compitition. Even though you may be pay $0.15 or what ever per kWh, you will only get like $0.04 per suplus kWh. It varies form location to location.

For the most part, the systems being built are heavily funded with grants and tax incentives to help offset the initial costs. Its too much for the average Joe homeowner to do on his/her own. Its still too cost prohibitiive.

I cannot accept the statement that the PoCo chrges retail and pays wholesale.

Rather, I am aware of the many states that have 'net metering' laws. That is, the PoCo pays you the same rate that they charge you. Period.

True, there are limits; typically the PoCo will not 'buy' more than you use - or will issue you credits, rather than write you a check.

Less obvious is the fact that even if you used ZERO power from the PoCo, you'd still be 'on the hook' for all the 'non KWH' fees and taxes that are added to your PoCo bill. For most of us, these additional charges represent a third of our bill!

Let's face it ... as 'evil' as the PoCo may be, it has only been made worse by all the political interference that has occurred.

It is reasonable that the PoCo still passes on all of it's fixed costs to the PV customer. After all they still need all that infrastructure for you at night. You are really only saving them the fuel charge.

Congress wrote a law years ago that stopped the Poco's from billing retail and buying wholesale.

BOTH prices are regulated.

That is why your bill is 20 separate line entries. They can say the "retail" part is just the fuel charge and the usage charge. All the other stuff gets passed straight through.