Priligy online now, save money

JUL 22

Recent Comment

"It's been debated since Edison and no prescription tramadol ups delivered Tesla, who lost over Edison's dirty..."

View all Comments

New Solar Panel Goes Straight To AC


The electricity that comes out of a photovoltaic panel is always DC.  Since our buildings tend to generic levitra online pharmacy use AC electricity, that means that a standard part of cialis best buy every PV solar installation is installing a big inverter to take the DC input from the panels and produce an AC output which is cialis discount identical to what’s coming from the local power line.

It’s possible, though, to build small inverters (aptly named microinverters) directly into each solar cell or module; instead of feeding all the electricity through a single, large inverter, you feed small streams of electricity through many small inverters.  

Startup GreenRay Solar is getting funding to develop this kind of technology, so that one day a homeowner can buy a solar panel and pretty much install it him/herself.  Right now, you usually have to be a licensed electrician to do the electrical work needed to install conventional panels.  But GreenRay’s panels would be a lot simpler, because they bypass the the best place canadian pharmacy viagra prescription inverter step.  It still might not be as easy as plugging in an appliance, but it would bring PV installation down a couple notches, within the reach of aspiring DIY-ers.

To answer the unasked question – yes, these solar panels will cost more money.  But, as GreenRay will tell you, microinverters offer additional benefits.  For example, if part of the panel is blocked, it will not affect the other parts.  And, if you are the kind of person who wants to viagra order no prescription carefully monitor your system’s performance, the microinverter panels will give you more precise and detailed information.  

However, as more and more electric devices require that electricity converted back to DC, and as PV electricity becomes more prevalent, one might wonder why we don’t begin to design DC houses from the start.

Via CNET Green Tech
Hits: 18431
Comments (17)Add Comment
This is new- but not that net
written by Steve A., July 22, 2009
These guys are a little slow out of the gate, as there are a number of products/panels already on the market that do this.

I personally think Andalay looks to have the best one, with integrated micro-inverters, and almost lego like rooftop construction. All you need is a typical AC wiring to the roof.

/does not work for andalay
written by Edward, July 22, 2009
My understanding is that DC is not practical if you're transmitting the power significant distances. However, if it's an "off-grid" situation where the production and consumption is localized to a single dwelling, it might make sense. However, installing an inverter still seems easier to levitra without perscription me than replacing all of your appliances with DC units.
written by haichen, July 22, 2009
another on:
May 18: Enphase Secures $22.5M in new funding
written by Bob Wallace, July 22, 2009
Edward - Actually just the opposite.

The most efficient way to transmit power long distance is DC. The world is viagra gel installing high voltage direct current (HVDC) transmission lines to move large amounts of canada drug cialis power long distances.

Because the technology needed to transform the power from AC to DC, ramp up the voltage, and crank it all back down to usable voltage AC was so wasteful "way back then" DC transmission was avoided.

But now the up/DC/down/AC process wastes less than 2% of the energy and that is recovered in more efficient transmission at distances greater than 250 miles or so.

A major HVDC line is the Pacific Intertie which carries hydro power from the Pacific Northwest to Southern California. And may soon be used to move thermal solar to major western cities.

And, as someone who lives 'off the grid' and gets ~90% of their power from solar panels, DC ain't the way to go.

One can't buy quality DC appliances/gadgets at value prices. It's cheaper to natural levitra buy an inverter and buy ultram online no prescription then purchase "normal" refridgerators, computers, shop tools, vacuum cleaners, etc.

I've got lots of friends who are off the grid in this area and I don't think any of them use DC for anything any more.

written by no one, July 23, 2009
A large percentage of electrical devices in the home run on DC. They have an internal AC to DC converter in order to plug into electrical sockets.
written by mike jones, July 23, 2009
This direct-to-AC solar is great.
More competition in this area is good also.
On that greenray site I don't see any info about any products (or a "buy now" button) so it seems like other companies are ahead of them.

written by OakleighVermont Solargroupies, July 23, 2009
First let me say that some of the commenters here know way more about electricity than I do. As someone who tests and sells renewable energy devices, it seems that it would be a huge breakthrough to be able to plug NAY device in to the sun and run it. Each cell phone, PDA, light, mp3, etc has a different adapter.. one mor thing to buy, and replace when you get a new unit. Let's standardize everything so everyone can and will use them.
written by Edward, July 23, 2009
Well...I'm currently renting, and can't do a lot of extensive modifications to where I'm living, but a friend of drug levitra mine bought me a Solio portable solar charger. I use it to charge my cell phone and iPod. It's more of a novelty than any meaningful reduction in my "carbon footprint" but I think it's pretty cool anyway. One of these days, I'd like to get a home PV system. I'm currently investigating the possibility of installing a PV system at my church.
written by mark, July 24, 2009
The laws here require mains voltage work to be done by a licensed electrician... So unless you can just plug these into a power point (already possible with some models of seperate inverters) it's not going to be DIY. Also I don't think someone with the know-how to install their own solar panels actually would have a problem with also installing an inverter.
Where this design is a breakthrough is in saving contractors time. Your local sparkie (electrician) already has a lot of experience with mains wiring, and a lot less with DC solar wiring. This design means they just do mains wiring.
written by Fred, July 24, 2009
this is probably very effective during the gay viagra summer
DC power distribution
written by EMerge Alliance, July 24, 2009
Allowing direct access to DC is safer and more efficient. Not too mention more sustainable, reducing the amount of materials needed (no AC-DC conversion components). This is why we created an open industry association promoting the rapid adoption of safe, low voltage DC power distribution and follow link get levitra cheap use in commercial building interiors. We recognize that commercial interiors are home to more and more digital, DC-powered devices that operate at less than optimal efficiency in an aging, AC-based building infrastructure. The EMerge Alliance is currently focused on developing a global standard that facilitates the direct connection of native DC power from solar, wind, or other alternative energy sources and improved efficiency through integrated load and source management.

Learn more about the benefits of DC power distribution at
written by Bob Wallace, July 24, 2009
Why is DC safer?

Because DC lines would be lower voltage? (Which would mean having to we choice buying viagra in canada run larger guage wire to carry the power.)

I'm divided on DC lines in houses. I can't see switching everything over to AC. It would take trillions and trillions of dollars. Every refrigerator, every washing machine and dryer, every electric stove/microwave, every TV, ....

I can somewhat see running a dedicated DC line for cell phone/laptop type charging. But that would mean a second set of wires and outlets.

Power bricks/converters have become very efficient and are inexpensive. If we were to standardize voltage/plugs then one brick per room would be all that most people would need to be happy.

And does the hardware exist to 'voltage-level' DC input sources? The value in putting separate inverters on each solar panel/wind turbine means that whatever power being generated by each device can be utilized.

Right now if one connects multiple DC PV panels and one is poorly producing, say due to temporary shade, the rest of the array's performance is badly degraded.

Inverting to buy viagra professional a standard voltage at point of harvest means that each device contributes what it can without pulling down other devices.
converter efficiencies
written by Marcel Geers, July 29, 2009
What I havn't seen anyone mention yet is efficiency. One of the "properties" of common ac/dc converters is that they are designed for a specific load (power usage). Meaning that you have your peak efficiency at a design load. Off course, you can tweak the online viagra sales controls of the converter, play with the topology, resulting in a broader spectrum of original levitra loads that still get a "decent" efficiency. Still, larger converters will be more efficient than many tiny micro converters. From an economic perspective, I very much doubt that this solution will benefit the already long ROI of solar panels.

Converter efficiency is something overlooked alot of the times. One or two years ago, the power supply of my ready-to-be-expandend-but-never-did PC failed. It was a 380W supply. It was already overdimensioned for the hardware I have and order viagra from canada thus was most likely underperforming. A new "eco friendly 85%+ efficiency" supply replaced it. However, the smallest one I could find was 420 or 450W (not sure how much it is as I'm lazy at this moment). I'm doubting very much that it is operating at 85%. I don't want to fiddle with current and voltages probes to compare the before and after power outputs, but perhaps any of the blog readers has done it?

DC Safety
written by Marcel Geers, July 29, 2009
One of the issues with low voltage DC on a household level is interruptabillity. With many devices present using say a standardised DC voltage (which most likely means that alot of AC/DC converters will be replaced with DC/DC converters), the fault-current detection will be set to a vary low level in this installation, as some appliances will use tens of mA while others will use several Amps. When a DC current is suddenly interrupted, the current will want to keep on flowing due to inductances in the current loop present. In order to have a nice and steady voltage in your system, a system capable of powering multiple appliances at once, there will most likely be a large capacitance and thus a large amount of charge present in the system. Interrupting a DC load (i.e. pulling out a plug of a gaming PC drawing quite some power) could thus result in some very nasty side effects compared to AC power, which goes to a zero voltage level 5060 times per second.

Perhaps it has already been thought up and I don't know about it, but in my point of view, it would require some accident proof wall sockets and plugs (something that can be thought up easily) and a clever short circuit topology to combat these issues (something I havn't heard of yet).

Feel free to shoot my comments, I'll enjoy reading your replies!

written by Vic, July 30, 2009
I read about solar panels lik,e this years ago.
dream on
written by Tony Nguyen, July 30, 2009
PV cells are similar to a diode, and are low voltage device for high efficiency. Inverters micro or not need high voltage MOSFETs and rectifiers. Those processes are incompatible with each other, therefore dream on. Some stupid VC may put in some money - good luck.
AC vs DC
written by Tony Nguyen, July 30, 2009
It's been debated since Edison and Tesla, who lost over Edison's dirty trick.

Depending on the application, there're pluses and dosage cialis minuses on both sides.

Write comment

security code
Write the displayed characters


Are you an EcoGeek?

We've got to keep 7 billion people happy without destroying our planet. It's the biggest challenge we've ever faced....but we're taking it on. Are you with us?

The Most Popular Articles