Before we get into today’s tip, let’s take one more look at the percentages of energy use in an average home:

29% Heating

17% Cooling

14% Water Heating

13% Appliances

12% Lighting

4% Electronics

11% Other (external power adapters, telephones, set up boxes, ceiling fans, vent fans, home audio, ovens, microwaves, small appliances etc. Basically all the little things plugged in around your home)

How can you affect that 12% of Lighting energy use?

Tip #2 Light Updates: Reducing your overall energy use where lighting is concerned is as easy as changing your lighting – update to energy efficient fixtures and get rid of those incandescents! Also, turn off lights in rooms when they aren’t in use and utilize natural daylight during the day instead of electric lighting.

We have a whole section on lighting in our blog with helpful information. So, check it out if you have questions about what kind of lights are most efficient, or if you want to learn more about daylighting.

A light shelf is a horizontal shelf-like light reflector, which can be mounted inside or outside of a window. It helps reflect daylight into areas that are farther away from a window, and also helps to make this daylight less direct and more diffuse. Although mostly used for commercial buildings, light shelves could potentially be suitable for homes, especially for large spaces like family rooms.

Light shelves are placed at least seven feet above the ground. This is to prevent having light reflected right into your eyes, and to make sure you don’t bump your head. Light shelves can be used with regular windows, but are also useful below skylights and clerestories. By diffusing the light they reflect, light shelves help to reduce glare. Although the shelves are normally a metal material like aluminum, the rougher and less mirror-like the surface of the shelf, the more diffuse and pleasant the light becomes. Experimentation with other light shelf material has included frosted glass, which helps bounce the light while allowing some light through it.

If made from metal, light shelves are thermal conductors, and could possibly aid in transferring heat and cold through windows into your home. This is a problem for our climate where most of the year’s weather is extremely hot. But with more experimentation and innovative thinking, light shelves may become a great feature for bringing in daylight into your home.

Another way to bring more natural light into a space is through skylights located in the roof of your home. If you have rooms with vaulted ceilings or no attic space, you can have skylights that light the rooms directly from the roof. If this is not the case, you can also have part of your ceiling recessed to allow for these skylights. When this recess is painted white or a light color, it aids the skylight by helping to reflect daylight into your space.

Skylights can be fixed or operable — they are normally only operable if they are within reach. Operable skylights can remove heat that rises towards the ceiling when other lower windows are opened for breezes, passively cooling your home.

Solar tubes or light tubes are an interesting developing version of a skylight. These are comprised of a glass dome that collects light and a rigid or flexible tube that reflects the light. Tubes are best for spaces with no direct roof access, as they are designed to fit through your attic. Solar tubes end up looking like large pocket lights in your ceiling, but instead of being electrically powered, they are sunlight powered. However, solar tubes are uninsulated and their metal tube is a thermal conductor of  hot or cold, potentially affecting the comfort and heating/cooling loads of interior spaces. As a result, the product needs a little more development before being an efficient day-lighting option!

Because skylights are directly inserted into the roof plane, there is a danger of leakage. Depending on placement they are also more likely than regular windows to receive direct sunlight (and thus heat gain). Skylights that are made with efficient material methods like double pane glass and low-e coatings can help combat this negative effect, but it is best if possible to restrict them to North facing areas. Remember that adding skylights to your existing home requires making holes in your roof. This can be a tricky process, but when done correctly and carefully can result in spaces with more beautiful daylight that you can enjoy.

Windows are normally placed low on walls so that their views can be seen when you are standing and sitting. After all, windows are just for looking out of… right? While this is true, another primary function of windows is to allow light into rooms. Clerestory windows, used in conjunction with normal windows or by themselves in certain situations, are a good way of bringing in more daylight.

Clerestories are windows above eye level, high on walls, which were originally used in ancient religious architecture like basilicas and cathedrals. Bringing them into your home is yet another instance of incorporating good, green ideas from the past! As these windows are easily shaded by roof overhangs or trees, clerestory windows can increase daylight without increasing heat gain and energy loads. These windows should be placed carefully—the north walls of your home are the best place for clerestories as there they allow in light without the chance of direct sun (and heat gain). If shaded properly during the summer, south walls are also a prime spot for clerestories.

Don’t forget that clerestories windows should be efficient windows too! Refer to our recent blogs about choosing windows and window characteristics for helpful information.

If operable, clerestories can help with natural ventilation. Cool breezes enter from windows lower down on the wall, move through a room, and push hot air out of the clerestories. This is a passive way of removing heat that would otherwise have to cycle through your air conditioning systems.

Overall, increased daylight brought in with clerestories can increase your happiness and physical health, while decreasing your energy use. More natural daylight means less electric light is needed during the day! Its a green building idea worth considering for your home.

Do you know the difference between ambient light and task lighting? And what do they have to do with green home design?

Defining the Two Kinds of Lighting

Ambient light is a general, soft light that fills an entire room, commonly from an overhead fixture. Task lighting on the other hand is for specific locations to focus light near work surfaces (like countertops and desks) or seating and beds for things like reading.

How This Relates to Green Design

Remember, green design is as much about careful thinking and planning as it is using green products and materials. By incorporating and allowing for both ambient and task lighting in each room of your home, you can light more effectively and therefore more efficiently. And you can also improve your health by being kind your eyes through always having the appropriate amount of lighting any need.

By having separate fixtures with separate switches for ambient and task lighting, you can reduce your energy use while still receiving necessary light. If you have multiple lamps or under countertop lighting in an area for a variety of tasks, think about also separating these with different switches or power cords so you can selectively control what light is in use (and drawing power).

Keep in mind that the further away a light, the brighter it needs to be. An ambient light source is normally much brighter than a task lighting source. Thankfully, improved light bulbs choices such as CFLs and LEDs allow this brightness to come at less Watts (energy used) than traditional incandescent bulbs. So, you can save energy and money and still have a brightly lit space. Having overhead fixtures that bounce light of the ceiling also helps to diffuse the light more pleasantly and imitates the brightness of the sky above us (making your room feel more comfortable and natural). Daylight is also a great source of ambient light and is especially good for your well-being. There are building methods for bringing daylight into a space without increasing heat gain, preventing higher cooling loads and energy consumption from that area.

Whenever you are considering remodeling or making changes to your home, remember these two different types of lighting. Their combination will not only make the rooms in your home more useful but also more comfortable and more efficient.

Lighting is a crucial part of our lives – we need it to complete the myriad of tasks that fill our days and evenings. As great as incandescent bulbs are for first bringing us electric light, more efficient bulbs are now needed to light our homes.

You all, hopefully, know about Compact Fluorescents light bulbs and use them in the most trafficked light sources in your home. These bulbs use ¼ of the energy that incandescent bulbs use to produce the equivalent amount of light. CFLs can even last ten times longer! If you’re concerned about how to pick from the range of CFLs available for purchase, see our article about selecting the right CFLs to help you choose bulbs for varying fixtures and spaces.

The new kid on the block of household lighting is a bulb containing LEDs. These bulbs contain many small Light-Emitting Diodes (what LED stands for) that illuminate when electrons (what electricity is composed of) move through their semi-conductor material. What’s interesting about these bulbs is that they emit heat and light in single (and opposite) directions instead of all directions. This means you can have the light you need without unwanted and wasteful heat, made possible by a built-in self-managing heat sink. Phillips has the first Energy Star approved LED bulb that uses only 12.5 Watts to produce the same amount of light as a 60 Watt incandescent. That’s 80% less energy used! Think about what that means for your utility bill! This product is also supposed to last up to 17 years if used for 8 hrs a day! LED’s are being developed into different varieties of lighting for different fixture uses. It’ll be interesting to see these new lighting products (that can potentially bring us the brightness of light we need without the large waste of energy) continue to be developed, tested, and brought into the consumer market for our use.

Did you know that If every American household replaced just one light with an ENERGY STAR light, we would save more than $600 million in annual energy costs, and prevent 9 billion pounds of greenhouse gas emissions per year Read More »

Unfortunately, choosing the right CFL is more complex than choosing the right incandescent bulb.  With a CFL you can choose the color spectrum of light.  CFLs are more affected by things like vibration, moisture  and heat. Read More »