AC driven LEDs are rare but popular in certain applications. Designers focus on LEDs because of their advantages like direct, brilliant light, strong color saturation, slim measurements, dynamic lighting scenes and in total all the design possibilities that are thinkable. The only restrictions are made by the heat that needs to be dissipated by surface, natural or forced ventilation and the driver’s measurements. The driver is mostly not slim at all. That is why AC driven LEDs can be a smart consideration.

Conventional LEDs, Modules and Light Engines are driven by DC (direct current) power supplies. The LED characteristics are highly dependent on these components as they control the inrush current, convert the alternate current down to DC voltage and stabilize the current the LEDs are driven with. The efficiency of the system is dependent on the driver too as the power factor is one part in the total sum. Most conventional DC power supplies support LED systems with power factors (PFC) of 0.9 and higher.

The lifetime of LED lighting systems is defined by electronic devises. The LED can last up to 100,000h but if the driver needs a replacement after 50,000h the system is only half worth the maintenance. Without any driver at all the problem is solved completely. Power supplies need space, no matter how small, the driver is mostly bigger than the LED modules and electronic component’s wiring needs space too. Without this item there are not restrictions in design any more than heat dissipation. Designers can release their full creativity.

AC driven LEDs are of advantage concerning design and lifetime options. The more complex the circuit, the higher the possibility of system failure and electrical noise. On the other side, the efficiency of AC driven LED modules is not that high like DC driven ones. The performance achieves 110 lm/W these days which is good compared to other light sources but behind DC driven LEDs with up to 140 lm/W and more. AC driven LEDs are a thinkable substitute in applications like bulb lights, downlights, ceiling lights and industrial lighting systems.

You might be thinking of buying one of those new-fangled electric cars, and may be wondering how they’re charged. That depends on which car you buy. The three main electric cars (electric vehicles or “EVs”) currently available for middle income families are the Toyota Prius, Chevy Volt, and Nissan Leaf.

Toyota Prius. Let’s say you buy a Toyota Prius. The Prius is a “hybrid.” A hybrid isn’t fully electric. It runs on electricity generated by a battery until the battery is depleted. Then, it turns to burning gasoline. In the case of the Prius, a 2010 model drives about 12 miles on a fully charged battery. But the Prius is continuously recharging the battery with a mechanism triggered by stepping on the brakes.

On the downside, the Prius currently doesn’t come with a “plug in” option. That means you can’t plug it into an electric outlet to charge its battery. However, Toyota is partnering with the EV company, Tesla, to develop a plug-in model that will be available in 2012.

Chevy Volt. The Chevy Volt, which started deliveries in the U.S. in December 2010, is also a hybrid. Unlike the Prius, the battery is not charged when you brake, but by plugging into the electric grid. It has a range of around 35 miles before it must start burning gasoline.

Nissan Leaf. The Nissan Leaf is currently the only all-electric EV available for middle income families. It can’t burn gasoline, but runs only on its battery. It has a range of about 100 miles before you need to start looking for an electric outlet.

HOW DO YOU CHARGE A PLUG-IN ELECTRIC CAR?

Level 1 Charging. Both the Chevy Volt and Nissan Leaf come with a charging cord, called a “Level 1 Charger,” as standard equipment. It looks like an extension cord. You can charge your car by plugging the Level 1 Charger into an electrical outlet in your garage or carport.

The advantage of Level 1 charging is that it’s simple and inexpensive to set up. Hire an electrician to install an outlet in your garage or carport. It will need to be on a dedicated circuit, meaning that no other appliances, like a washer, for example, are on the same circuit. The outlet will need to be the safety version usual in garages and outdoors (a GFI). Also, your electrician will need to check whether your electrical panel should be upgraded in size to handle the increased power demand.

Once the outlet is installed, the EV driver pulls out the Level 1 charging cord that comes with the car, starts charging, and lets the car sit… for a long time. A Chevy Volt battery takes 10 hours from empty to full; a Nissan Leaf takes 20 hours.

Even though Level 1 charging is slow, drivers who have short commutes may be satisfied with it because, if they work it right, they won’t start at empty. They’ll have charge left in their batteries and will simply top off at night.

Here’s how it can work. The 100-mile range of the Nissan Leaf is a lot more than the 33 miles the average American drives daily. If you drive the average 33 miles, you will use only one-third of the battery in a day. If you religiously plug in when arriving home, you will be able to top off at night and leave with a full charge in the morning.

For hybrids, like the Chevy Volt, the issue of leaving home fully charged is less pressing. At about 35 miles, when the battery hits empty, it turns to burning gas. This isn’t good for gas usage, but on the other hand, the driver may suffer less from “range anxiety.”

Level 2 Charging. While you may be able to make Level 1 charging work for you, you also have the option of faster charging by installing a special Level 2 Charger in your garage or carport. A Level 2 charger takes a Chevy Volt battery from completely empty to completely full in four hours; eight hours for the Nissan Leaf. So, even if you totally drain your battery, with a Level 2 Charger, you’ll be able to fill it by morning.

A Level 2 charger requires 240 volts, which is more powerful than house current. A Level 2 Charger is housed in a container about 18 inches around and hangs on the garage wall, sticking out about a foot. When you recharge with a Level 2 charger, it looks very much like filling your tank with gas. You stretch a “hose” over to the recharging socket built into the EV.

A Level 2 Charger is usually purchased when you buy your electric car. If you wish, Nissan or Chevy can arrange the purchase and installation. Nissan has partnered with AeroVironment to supply and install chargers. Chevy Volt has partnered with SPX. When a Leaf, for example, is purchased, the Nissan dealer arranges for an AeroVironment electrician in Los Angeles to look over the new owner’s garage, provide a bid, and do the installation.

The car buyer is free to look for a lower bid from an independent Los Angeles electrician; however, warranties and follow-up repairs on the charger may not be as advantageous.

Consumer Reports estimates that purchase and installation of a Level 2 Charger costs about $2,000. However, the price can vary quite a bit, depending on the distance of the charger from your electrical panel and on whether you need an upgrade of your panel size to accommodate the additional power demands of the charger.

THE FUTURE OF CHARGING YOUR ELECTRIC CAR

Level 3 chargers that can fully charge a Nissan Leaf in 15-30 minutes are currently available in Japan. However, they cost about $45,000 installed. When they come to the U.S., they will most likely be installed for electric trucks, company fleets, or for private cars at shopping malls and at gas stations, where EVs will zip in and out to top off their batteries.

An even faster system is currently being installed in Israel. A Palo Alto company called “Better Place” is building a network of “carwashes.” Only, when you drive your EV in, instead of getting a wash job, your spent battery is pulled out and within a couple of minutes, is replaced with a fully charged battery.

The pressure to be fully charged when leaving home will ease as chargers are increasingly installed in public places in the U.S. In my hometown, Los Angeles, Level 2 Chargers are already available in train stations, the main airport (LAX), the L.A. Convention Center, and other public places. One can easily find the network of existing public chargers on-line. In addition, malls will begin installing Level 2 or Level 3 Chargers as an inducement for shoppers and workplaces as an employment benefit.

Click here to visit our website.

In all the hustle and bustle of the day, it’s easy to get sidetracked or to not pay close enough attention in the kitchen. In a matter of just a few seconds, your kitchen can go from being the heart of your home to being a disaster zone. Every year, there’s a significant spike in home fires on Thanksgiving and Christmas. Ensure the safety of your family by following these tips!

We know that today may be incredibly busy for you, so we wanted to do our part to help make it easier. We’ve created a printable graphic that you can pin to your refrigerator to remind you of the important tips you need to follow.

Everyone probably knows light layering is the #1 rule in residential lighting design, but we can often neglect it in professional settings. Light layers can transform that standard gloomy, fluorescent malaise into something calm and energizing.

2. Take the layers outside too! The center’s entryway functions like a beacon in the night with those stylish ceiling lights, along with Image via CONTEMPORIST.com

If your business has a storefront or entryway, don’t neglect eye-catching light layers there either. You want to draw customers in, not scare them away.

3. Use standard fixtures in unexpected ways. A regular fixture in an unexpected place will be avant-garde, without the price tag of an avant-garde light fixture. Image via CONTEMPORIST.com

I’d also like to note those crazy recessed ceiling lights – totally echoing a standard recessed fixture only stylized and amplified. It makes you rethink the whole concept of a regular old recessed light!