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DOE issuing guidelines on sale of solar panels


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rainymike

If you're considering solar ... it's probably not the best time for noobs like myself to jump in. The stuff that I've seen at hardware or electronics stores might be okay for garden lamps, but overall hasn't seemed all that inspiring to me.

 

http://www.philstar.com/business/2015/07/19/1478486/doe-issuing-guidelines-sale-solar-panels

 

 

 

MANILA, Philippines - The Department of Energy (DOE) would draw up standards and guidelines for the sale of solar panels amid complaints on the products out in the market.

 

“We’re in the process of coming out with standards so we can guide the consumers (in buying solar panels),” said DOE OIC-Secretary Zenaida Monsada said in an interview.

 

While it is a welcome development that a lot of companies are selling solar panels, Monsada said the agency has received numerous complaints about products that only work for a few months.

 

“There are now a lot of solar panels in the market but we are receiving a lot of complaints,” she said.

 

Monsada noted the DOE would work with the European Union to draft standards for the sale of solar panels.

 

Meanwhile, the DOE is looking for more projects under the Solar Rooftop Facilities in Academic Institutions as it pushes for the use of renewable energy.

“We started this project with schools so the schools are able to save in electricity usage. For that pilot project, the schools did not spend for anything. Now we are discussing for more of these projects,” Monsada said.

 
“We started this project with schools so the schools are able to save in electricity usage. For that pilot project, the schools did not spend for anything. Now we are discussing for more of these projects,” Monsada said.
 

So far, St. Scholastica’s College – Manila, La Consolacion College – Manila and Manuel Luis Quezon University have participated in the project.

 

The DOE aims to install up to 100 kilowatts rooftop solar photovoltaic systems to help schools lower their power costs.

 

Overall, the agency hopes to double the country’s total renewable energy installation of 5,521 megawatts.

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Paul

People want to have reliable electricity, whether for off-grid or when the mains power is down. But, they don't want to put the money out for a proper installation. So, they buy cheap shit that was designed to last for a week, then complain because it only lasted a week. :rolleyes:

 

In my opinion, if people don't have the cash to pay for quality components to begin with, they should either save up for them, or start with a smaller installation. 

 

When buying products for a solar installation, you do not want to skimp on the parts that are going to provide power for you during emergency situations. 

Well, that's my thought regarding it, anyway. 

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KennyF

It seems to me, from what I've heard and some experience, unless you NEED to be off the grid, one is better off financially to go with the grid.

Payback or break even for solar takes quite a long time.

Over 10 years in some cases.

Which probably means the stuff you installed is well out of date before you get ahead

And it's probably worth noting that many members, including me, don't stay in one place that long anyway.

 

KonC

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Paul

It seems to me, from what I've heard and some experience, unless you NEED to be off the grid, one is better off financially to go with the grid.

Payback or break even for solar takes quite a long time.

Over 10 years in some cases.

Which probably means the stuff you installed is well out of date before you get ahead

And it's probably worth noting that many members, including me, don't stay in one place that long anyway.

 

KonC

 

It used to be that panels were the most costly part of a solar system. Now, it's the batteries, because panels have dropped in price so much over the decades. (In the US, for example. You can get panels purchased and delivered to you, for well under $1.00 USD / watt, nowadays.) 

 

Grid-tied is definitely the best, fastest way to recoup your investment, due to not having to install a costly battery bank along with the panels. No initial outlay for batteries. No battery maintenance. No battery worries. 

 

However, there is one major drawback about a grid-tied system. That is when the grid goes down. When the grid drops out, so does all the power feeding your home. Then, you have all those fancy panels on the roof, completely capable of generating all sorts of power, but are of no use to you whatsoever. 

 

I imagine a hybrid system would be the best way to go, if you wish to have power during mains power cuts. At least in areas where you are not forced to go off-grid with your array. 

 

Before I left for the US, my system ran my electronics 24 / 7. One battery died and the other exploded, while I was in the US. To replace those batteries would be an outrageous cost to me. So, I am going to go with a smaller battery bank, one that will ONLY provide emergency power, when the mains are off-line.

 

When power is disconnected at the mains, my electronics will automatically be switched to the back up sine wave inverter, providing all power needs until mains power returns. This will require a much smaller bank than previously necessary. And, I will now have more power coming from my solar array than I actually need. So, I will see about wiring in some sort of dump load to keep the array busy during times of excess power. Maybe a single element water heater? Who knows?

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Headshot

However, there is one major drawback about a grid-tied system. That is when the grid goes down. When the grid drops out, so does all the power feeding your home. Then, you have all those fancy panels on the roof, completely capable of generating all sorts of power, but are of no use to you whatsoever.

 

Well, I don't think that is completely true, is it? Most utilities in the US require that you install an automatic disconnect if you are going to connect any kind of generation to the grid. That means that when the power in the grid goes off, the automatic disconnect isolates your generation from the grid (to keep the line workers safe). As long as the generation is hooked to the same side of the automatic disconnect as your home, you will still have power in your home from the solar panels. If you set up the automatic disconnect to isolate the generation from both the home and the the grid, then your home is, indeed, be without power whenever the grid goes down. That would seem like a silly way to do things to me. Of course, without batteries, you will be without power when the sun goes down regardless of how the automatic disconnect is configured.

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Paul

Well, I don't think that is completely true, is it? Most utilities in the US require that you install an automatic disconnect if you are going to connect any kind of generation to the grid. That means that when the power in the grid goes off, the automatic disconnect isolates your generation from the grid (to keep the line workers safe). As long as the generation is hooked to the same side of the automatic disconnect as your home, you will still have power in your home from the solar panels. If you set up the automatic disconnect to isolate the generation from both the home and the the grid, then your home is, indeed, be without power whenever the grid goes down. That would seem like a silly way to do things to me. Of course, without batteries, you will be without power when the sun goes down regardless of how the automatic disconnect is configured.

 

All states will require you to have an automatic disconnect to protect people down the line.

 

A grid tied system uses the grid as its "battery bank". Without the batteries how will the panels continue to provide power to the house circuits?  

 

 

Hybrid

batt_backup_full.jpg

 

Off Grid

24v_inverter.jpg

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The only thing the battery bank gives you is stored power at night when the solar panels are not generating. Everything electrical in your house will continue to operate even without batteries...as long as the sun is shining. When the sun goes down, then everything stops working unless there is a battery bank. Some people think that there has to be a perfect balance between supply (current) and load, while in fact, there is seldom a perfect balance. The supply does need to be equal to, or greater than, the load...but they don't have to be always equal.

 

A lot of overcapacity (more current than needed) in an off-the-grid system would be a waste of money, if there was always an overcapacity, but that is seldom the case with a solar system that is tied to the grid, since the excess generation will flow into the grid. However, the overcapacity won't hurt anything if the system isn't tied to the grid during a grid outage. Your electrical stuff in your house won't suffer any damage due to an oversupply. Each load (light bulb, refrigerator, washing machine, power drill, whatever) will only draw the amps it needs.

 

Think of it this way...you may have a 20 amp breaker feeding a circuit in your house. Now, it is unlikely that anything on that circuit will draw 20 amps, but the circuit could provide up to 20 amps if needed. The electrons only get excited enough to move when there is a load that draws them...no load...no flow. Your solar system is the same. It will provide anything up to its capacity...but not over. But unless there is a load to draw current, the electrons won't get excited enough to move.

 

With an off-the-grid system, you need to always have a little bit of overcapacity, since bad things do happen if load exceeds supply, but you try to calculate the generation capacity to be just a little over load requirements. With a grid-tied system, the calculations are different. In fact, a lot of people just use solar generation to supplement the grid power they receive. In those cases, you need to shed non-essential load prior to making the switch, since at any given time you might have more load than capacity. If, however, your solar generation system is built to take whatever normal load you have, then there is no need to shed load before switching over.

 

When things (electronics mostly) blow up is when you get over-voltage...not excess current. Over-voltage most often comes from lightning strikes, or phases coming together, that sends a surge through the grid. It can cause an outage, but that is a hazard of being tied to an improperly grounded grid. Having your house disconnect from the grid doesn't generally present any additional hazards to the electrical stuff in your home.

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Paul

Bill, if I may ask, how many grid tied solar systems have you installed? I have installed zero. So, I feel I am arguing a point that I am not really qualified to argue. However, I do know the basics of these systems. And, I have installed several off-grid systems at this point. I also know the total output of a solar array is going to change throughout the day - over the course of seconds, even. So, without a battery bank, the solar array would have to constantly provide more power than is being drawn, in order to constantly run your entire home. 

 

What happens if this scenario plays out? The mains drop out. You have say, a 5 kilowatts array, generating 60% due to a partially cloudy day. What is going to keep your appliances running evenly as the wattage output of that array varies from cloud cover, to open skies? Your home is drawing 100% of the generated power. But, what happens when the sun is blocked by passing clouds and the array output drops, even for a minute, to say 30% output? Your electrical appliances would be pulsing at best, burned up at worst.

 

So, I have to ask, what experience you have in this, to prove what you are saying. Again, I haven't installed any grid-tied systems. But, I know enough to know that there must be some way to have stable stored energy to run the inverter(s) feeding your home.

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Bill, if I may ask, how many grid tied solar systems have you installed? I have installed zero. So, I feel I am arguing a point that I am not really qualified to argue. However, I do know the basics of these systems. And, I have installed several off-grid systems at this point. I also know the total output of a solar array is going to change throughout the day - over the course of seconds, even. So, without a battery bank, the solar array would have to constantly provide more power than is being drawn, in order to constantly run your entire home. 

 

What happens if this scenario plays out? The mains drop out. You have say, a 5 kilowatts array, generating 60% due to a partially cloudy day. What is going to keep your appliances running evenly as the wattage output of that array varies from cloud cover, to open skies? Your home is drawing 100% of the generated power. But, what happens when the sun is blocked by passing clouds and the array output drops, even for a minute, to say 30% output? Your electrical appliances would be pulsing at best, burned up at worst.

 

So, I have to ask, what experience you have in this, to prove what you are saying. Again, I haven't installed any grid-tied systems. But, I know enough to know that there must be some way to have stable stored energy to run the inverter(s) feeding your home.

 

I have installed exactly zero. I studied it a long time as part of my job, but I have never seen it as a viable option for me because of the cost and lifespan issues of the equipment. Basically, if you are on a fairly reliable grid system, you probably will never see a return on your investment. Of course, if you are off the grid, or on a very unreliable grid system, then the numbers change, since peace of mind has to be worth something. And, of course, the numbers are changing as the price comes down.

 

However, I worked in Distribution Engineering for Pacificorp for 15 years, and we had to figure out the ins-and-outs of how customer-owned generation connected to our grid. So, I understand fairly well how distribution systems work, and how they interact with customers. I have watched several solar generation systems being installed to the grid, so I think I understand the basic mechanics, but I don't consider myself an expert on the subject. You can certainly correct me if I'm wrong.

 

As to your question on what to do when the grid drops out and you are generating 3 kilowatts, I would suggest that you will probably have to cut way back on what electricity you are using (although I have no idea how much electricity you usually use. In other words, you shouldn't be operating close to 100% of generation when you are operating off the grid (without batteries). Even with batteries, you need to cut back some if you want your batteries to last. I talked about overcapacity, and you don't want to waste generation capacity, but then you don't want to be close to that on load either. So, basically, if you install a grid-tied system, you have two choices. You can either over-install (so that you are generating more than you need) in which case you can continue on continuing on (keeping an eye on actual generation), or you can just install enough to run you essential services (so you need to shed all non-essential load when there is an outage). The thing you can't do is let the system load get close to capacity.

 

In your circumstances, it seems like a hybrid system (with batteries) would be best because a simple grid-tied system (with no battery bank) will not give you any power at night. That doesn't seem like it would be acceptable for someone who rarely sleeps.

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fred42
Well, I don't think that is completely true, is it? Most utilities in the US require that you install an automatic disconnect if you are going to connect any kind of generation to the grid.

 

 

From what I have read,grid tie inverters are designed to shut off power from panels going to the grid in a mains outage or brownout.

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Paul

I have installed exactly zero. I studied it a long time as part of my job, but I have never seen it as a viable option for me because of the cost and lifespan issues of the equipment. Basically, if you are on a fairly reliable grid system, you probably will never see a return on your investment. Of course, if you are off the grid, or on a very unreliable grid system, then the numbers change, since peace of mind has to be worth something. And, of course, the numbers are changing as the price comes down.

 

Actually, that is why people ARE going with grid-tied systems nowadays, more so than in the past. ROI is easier to get now and takes fewer years to turn over than in previous years. This is due to the serious drop in pricing on solar panels in today's market.

 

What you do NOT want to go with, if you can help it, is an off-grid system. It takes much longer, if ever, for you to recoup your investment. That's why it is always best to look at cutting back your current usage, rather than trying to build a system to support it. 

 

I will agree that the prices are coming down and numbers are changing. However, that is only applied to panels. Batteries are as expensive as ever, still causing (off-grid or hybrid) systems to be very costly, per kWh powered. 

 

As to your question on what to do when the grid drops out and you are generating 3 kilowatts, I would suggest that you will probably have to cut way back on what electricity you are using (although I have no idea how much electricity you usually use. In other words, you shouldn't be operating close to 100% of generation when you are operating off the grid (without batteries). Even with batteries, you need to cut back some if you want your batteries to last. I talked about overcapacity, and you don't want to waste generation capacity, but then you don't want to be close to that on load either. So, basically, if you install a grid-tied system, you have two choices. You can either over-install (so that you are generating more than you need) in which case you can continue on continuing on (keeping an eye on actual generation), or you can just install enough to run you essential services (so you need to shed all non-essential load when there is an outage). The thing you can't do is let the system load get close to capacity.

 

My home uses about 6 kWhs per day, over the course of a month. About 180 kWh's per month. 

 

But, unless you know exactly what everything in your home draws, there is no way, without the use of power meters, to determine how much power your home is drawing over any time period. Not to mention, I have an inverter refrigerator, which, basically, runs all the time. The difference is, it draws anywhere from about 2 watts, to 120 watts of power while running. Rice cooker, sandwich maker, blender, etc., etc., etc. You would have to be able to stay right on top of every appliance, and know exactly what it draws, in order to determine what can run, and what cannot, at any given time of day. This doesn't even take into account any shading or clouds that may reduce the effective output of the solar array.

 

Keep in mind that very little shading can cause a dramatic drop in solar array output. So, what you are saying here is - well, impossible to do. That is why, when a grid  tied system disconnects during a power cut of the mains, it also disconnects from your home. A power cut is still a power cut, although you may have more than enough solar array to provide all your power needs, on the roof. 

 

That is exactly why hybrid systems came into play, for those people who want to continue to have power, during a power cut. So, having a battery bank connected is not optional. Well, it would be optional. But, that would only apply if you ran a back up generator, thereby still making your array - useless during a power cut. 

 

Generating more than you need. I'm not sure what the requirements, or restrictions apply, concerning connecting a grid-tied system. I am pretty sure, though, that it would not be feasible to run, say a 10 kW array on a home that only needs half that over a 24 hours period. The idea behind going with a grid-tied system, is to balance out your power usage in hopes of staying at, or near a zero balance on your power bill.

 

Also, keep in mind that, when running a battery bank, you must generate considerably more than you will need to fill the batteries to full capacity. This, alone, is due to losses and inefficiencies in solar systems. Over all, end to end efficiency of an off-grid system is going to be somewhere around 52%. That is something many people do not even factor in, when setting up an array.

 

 

In your circumstances, it seems like a hybrid system (with batteries) would be best because a simple grid-tied system (with no battery bank) will not give you any power at night. That doesn't seem like it would be acceptable for someone who rarely sleeps.

 

Actually, the array here at my home in the city is an off-grid system. Before I left for the states, it powered my electronics (internet, network & computer) 24 hours per day. While I was away, I lost two large capacity batteries on my system. One exploded; the other died.

 

Now, I am changing the system to provide back up power only, for the same hardware. In the future, when the mains fail, a relay will de-energize and switch the circuits over to the (pure sign) AC inverter and a lower capacity battery bank. When power is restored, mains will continue to provide the power necessary to run those circuits. During the delay from mains to inverter power, the network and computer will run off UPS power, to guarantee no disconnection of AC power.

 

This will work fine for me, as our power cuts never seem to last more than 30 minutes to one hour, here.

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Paul

From what I have read,grid tie inverters are designed to shut off power from panels going to the grid in a mains outage or brownout.

 

Yes, that is correct. One plus when using a grid-tied system is, you can go with micro inverters, which can tell you exactly what each panel in your array is generating while connected to the grid. You can see before hand, when problems may be cropping up. Many issues can be sorted before a panel, or micro-inverter fails on your system. 

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rainymike

LOL ... you guys are talking way over my head. But I do know this is something that others with my level of knowledge (not so good) may have thought about. Just casually looking around at what was readily available, I really wasn't impressed with the panels that I saw. Again, I'm no expert but I had doubts about how long they'd last. 

 

Still seems too high cost and of uncertain quality for what I'd like. Best solution for me has been going with those small rechargeable portable fans/lights from Ace hardware. I was mostly concerned with lighting and cooling for a couple of rooms during the brief brownouts that we have where I live. We're outside the major hurricane zones. And the worst problem might be from a once a century type of big earthquake. The most realistic problem is that our city continues to grow rapidly and the grid cannot keep up with demand in the near future.

 

I still like the idea of solar, but seems that although new technologies are being invented, not all those technologies are on the market yet (here) or of the desired quality for me. Will keep my eyeballs open though.

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Paul

 

 

I still like the idea of solar, but seems that although new technologies are being invented, not all those technologies are on the market yet (here) or of the desired quality for me.

 

The reason people are complaining is, they want cheaper parts to install solar systems on their homes. However, when they buy cheap, junk is what they are going to get. And, let's face it. CDR King isn't known for being anything more than the "Radio Shack" of the Philippines. 

 

Something else people don't really think of, when buying these parts. There is a reason for spending money on quality parts - safety. You buy cheaply made parts, parts that do not pass any sort of proper inspection, and they can burn your home to the ground. When I purchased the panels I use here in Cambodia, I made sure they were from a reputable company. I made sure I checked to see what sort of service record they had. With CDR King, you can't do that.

 

Panels, controllers, etc., sold by CDR King are rebranded junk in the first place. If you want quality panels, go with a company like Kyocera. They aren't cheap. But, they are good. Another company I know about with a good reputation, is Yingli. Personally, I use Just Solar. Not too costly, a mid-ranged panel.

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thebob

I think we have reached a point in the product cycles that have introduced unneeded complexity at the expense of reliability. Sales gimmicks, and packaging have outstripped common sense.

 

When I see tiny enclosures containing switch mode controllers, heat sinks and power transistors, blinged out with LCD screens I smell disaster in the future.

 

A 500W PC power supply has slightly less than the capability of most of these controllers. They have large fans, they are noisy and are about half the size of a shoe box. They still only have a life expectancy of 3-5 years. Expecting to cram that into an extruded case, with mostly passive cooling with a tiny token fan, is all to do with marketing and shipping, not engineering.

 

Gaining a few percent "efficiency" with MPPT is meaningless if the added complexity means failure is going to kill your batteries, or short out your panels years before their predicted failure date.

 

These controllers need "tropicalising. Batteries need to be designed specifically for the climate here. Installation is far more involved than "just making it work". All single points of failure need to be eliminated, multiple redundancies built in.

 

Expecting a totally turnkey, off grid system to run maintenance free for years is just totally unrealistic at this point in time.

 

Buy a big enough piece of land, dig an underground generator room, far enough away from your house so you can't hear it. And install a "large" fuel tank. That is where the price point is at the moment.

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