CameraCapers: About lighting (two article in one)

CameraCapers: About lighting (two article in one)

Monday, November 17, 2008

About lighting (two article in one)

Making up for lost daylight

By Maria Stamas

Posted Fri Nov 7, 2008 11:10am PST

The sun is setting earlier in the northern hemisphere and for most Americans, clocks rolled back on November 2, stealing another hour of natural light.

Less time to both play outdoors and work window-side means more time for electric powered lights.

This is no small matter. A fourth of all electricity consumed in the United States goes toward lighting, and 20 percent of that is spent air conditioning waste heat from inefficient light bulbs. Plus, as my colleague Cher Seruto notes, the more artificial light used at night, the less stargazing for us all. (article inserted below)

Five ways to bring back the night

By Cher Seruto

Posted Fri Jan 25, 2008 3:12pm PST

Cher Seruto is an analyst with the Built Environment Team at Rocky Mountain Institute.

They are magnificent, present yet untouchable, the object of much affection. No, I'm not talking about celebrities. I'm talking about stars in the night sky.

This year, I spent the winter holidays backcountry skiing from a small hut in the national forests of southwestern Colorado, and the abundance of stars reminded me that I miss their presence in my city.

"Where did the night sky go?" I wondered.

We city dwellers often don't see many stars because of light pollution. Much of this obtrusive light is caused by excessive interior and exterior lighting from advertising, commercial properties, offices, factories, streetlights, sporting venues, and our own homes.

The effects of light pollution
It's very clear how development and light pollution are linked. NASA's night image of Earth (below) is proof enough.

Back on the ground, light pollution is pretty easy to spot too.

If you ever have the opportunity to look at the night sky from outside a city, scan the horizon. You can often see the direct effects of excessive lighting as a halo in the night sky.

When I lived in Santa Barbara, I would often walk the beach at night and look across the ocean. Instead of stars, I would see light emanating from the Los Angeles Basin 100 miles away. And at the Grand Canyon, you can see a similar halo from Las Vegas, 175 miles away.

Besides marring the view, light pollution wastes energy. The International Dark-Sky Association estimates that every year the United States wastes 110 billion kilowatt-hours, or $10.4 billion, on "ill-conceived, ineffective, and inefficient lighting."

Generating all that unneeded electricity to power those lights results in more greenhouse gas emissions that increase the threat of global warming.

Simple steps to reduce light pollution
With so much at stake, I'm happy to report that there are simple solutions to drastically reduce light pollution and save energy.

First, start at home:

1. Light only what you need. Ask yourself whether your lights are located in the right places for your daily needs. 
2. Light only when you need it. Use motion sensors to cut your electricity bill, and be diligent about turning off lights that are not in use. 
3. Light where you need it. Make sure that outdoor fixtures don't emit light upwards or excessively outwards. Proper lighting does not shine into the night sky or across to a neighbor's property. 
4. Light in the right quantity. Look at the effects of your outdoor lights. Are shadows created that actually obstruct vision? Lower the wattage and you may be able to see better due to the reduction of shadows. I recently installed a lower wattage motion detector light outside my back doorstep and was amazed at the increase in visibility. 
5. Check placement, curtains, and window coverings to make sure your indoor lighting is not shining out and up at night.

Next, encourage your workplace and local government to standardize the use of lighting techniques that decrease or eliminate light pollution.

You can find more resources and tips on reducing light pollution from the International Dark-Sky Association.

Lighting technologies have come a long way since the incandescent bulb, which wastes more than 90 percent of its energy as heat. Here are a few lighting tips to make the extra hour of dark in our evenings a moot point:

Smart Use First

Use lighting only when and where you need it. Lighting a whole room so you can see what you're doing is similar to refrigerating a whole house to preserve perishable food. Try using task lights instead. And if you can't remember to turn off lights, install occupancy sensors to do it for you when you enter or leave a room.

Efficient Lighting

Replace your halogen torchieres! Ever wonder why they create fire hazards? These lamps operate at 970 degrees Fahrenheit. Compact fluorescent (CFL) versions can save each year the carbon dioxide equivalent of driving a medium-sized car 743 miles. You'll also avoid $36 a year on your electricity bills. For cost-saving details see Rocky Mountain Institute's (RMI) Home Energy Brief #2 (PDF).

If you haven't switched out your incandescents for CFLs, don't wait another minute. CFLs save you money in two ways:

1. They last longer than incandescent bulbs (between 8500 hours and 11,250 hours depending on how well you use them), and
2. They use less electricity to provide the same amount of light -- only 25 percent as much.

Specifically, each CFL you install saves $50 in electricity costs over the lifetime of the bulb. If you replaced five 75-watt bulbs with CFLs, you could save more than $250 over eight years! See the American Council for an Energy-Efficient Economy's chart for details.

You could accrue even more money by switching out incandescent fixtures for CFL fixtures. If all households in the United States replaced five 100-watt fixtures with 23-watt CFL fixtures, enough electricity would be saved to power three cities the size of New York day in and day out.

Want to do more? Try purchasing some cutting-edge light emitting diodes (LEDs). These lights last ten times longer than CFLs. Decorative LED lights -- like those used to drape across Christmas trees -- use less than a dollar of electricity to operate over the holiday season and large strings of light can save up to $75.

And when your lightbulbs do burn out, don't forget to recycle them. The Home Depot and IKEA collect CFLs. Check out the EPA or Earth911.org to find your nearest recycling location.

Adding Natural Light

Beyond electric lighting, plenty of opportunities exist to add more sunlight. Daylighting lowers electricity use and cooling loads, and enhances our visibility, health, and productivity. Try these simple fixes:

• To reflect more light around your rooms, paint a wall white and switch out darker carpeting for lighter versions.

• Install a solar tube to funnel light into spaces with few windows like dark hallways, bathrooms, and kitchens. These fixtures are the low-cost alternative to skylights and are available for under $400.

• Mount a lightshelf. Lightshelves are flat surfaces attached to the exteriors of buildings that bounce natural light through windows and deep into the building while also reducing glare.

Designing from scratch or embarking on major retrofits? See how RMI architects have implemented their daylighting designs in homes, office complexes, and factories.

For more information check out RMI's Home Energy Brief #2 (PDF).

Maria Stamas is an analyst with Rocky Mountain Institute.

Blogged with the Flock Browser