Tag Archives: Energy Efficiency

The National Geographic’s 12 Step Energy Diet

Read this very interesting article in the National Geographic titled  “Energy Diet” under the topic National Energy Challenge. It is based on the Dutch language book, The Ideal Energy Weight, by Klaas van Alphen, a researcher at Copernicus Institute for Sustainable Development, Utrecht University and Herman van der Meyden, a Shell engineer who has participated in the company’s future scenarios project.

He came up with the book in response to the Three quarters of Dutch people who want to save energy. But where would they start? And what really makes a difference? The Ideal Weight Energy is the solution says Herman.

An energy diet pretty much is like a normal diet; I would know for how many ever diets I have tried I am always fighting with what I can and can’t do with out… You listen to all the experts, read all the books etc, but the thought of starting a diet can be daunting. Once you have tried a diet a new one with the term diet always triggers an array of questions: Will I feel deprived? Can I stick to all the changes I’ll need to make? And where do I begin?

The Energy Diet aims to help you take a step-by-step approach toward a lifestyle that is healthier for the planet, and may even end up saving you money. National Geographic has simplified it for us in a 12 step program, one for each month of the year. So if you want to give it a try, you are getting a head start 🙂 get set to make changes in the New year, after all it is only 3 months away!

These are the 12 steps:

  1. January Check the age of your refrigerator – replacing an appliance older than 10 years with a new energy star one will pay for itself in a couple of years!

  2. February Consider replacing your natural gas furnace or boiler with a high efficiency (HE) unit. Check out this link for helpful tips and links. Your power consumption and comfort level will improve substantially with the right HE furnace.
  3. March – Check your power bill, Do you have Green Electricity? See if Renewable energy is available where you live and where you can get the best deal.

  4. April – Summer is around the corner, planning your next vacation? Consider a green vacation, pick green hotels,Consider a “Staycation”. If traveling by flight consider buying carbon offsets A Green vacation is a good start to a Green year!  

    Staycation courtesy the New Ecologist

    Staycation courtesy the New Ecologist

  5. May – Energy saving power strips for all your electric gadgets from mobile phones to TV’s and Computers. Make sure you turn them off or unplug them when not in use. The plugged in devices drain power even when not used.

  6. June – Investigate the possibilities for installing your own alternative power source – Solar, wind etc… The US Government has many subsidies for individual Alternative energy production. There are also some Solar manufacturers who are willing to work with you to make owning Solar power affordable and viable. Check out Sungevity they have leasing options too!!

  7. July – Check your driving habits. Is your car giving you enough mileage? Are you doing the best you can about using public transport?  Calculate how much you could save with buying a new car? Will a Hybrid be a prudent buy?

  8. August – We are half way through, so this month is for Sun, Sand, beach and fun!

  9. September – It is almost fall, days are getting shorter that means more lights. Switch your bulbs to energy efficient CFLs, save energy and money in the long run guaranteed.

  10. October – Summer is a memory and cold fronts moving in slowly, perfect time to winterize your home. It will keep you warm and your heating bills low. Check for drafts near windows doors etc. The Insulation guide from US Energy department is of immense help.

  11. November – Winter is at the door step, check for holes etc which need closing. Use caulk or weather stripping. Remember to keep the fire-place damper closed when not in use. Also try and replace your decorative lights with LED strings will help in the long run. I am doing it one string at a time, so the amount I spend is not too hefty.
  12. December – It’s the holidays! Share your successful diet with friends and family! Enjoy your Green Holiday Season!

    So are you going on an Energy diet in 2011? It would be fun to hear back from you, if it does work out for you. I will update the post with my experiences next year. For my part I am almost done with the transition to CFL bulbs. I need to take care of the insulation before it gets too cold.

    You can check out the National Geographic article HERE

February Consider replacing your natural gas furnace or boiler with a high efficiency (HE) unit. Check out this link for helpful tips and links. Your power consumption and comfort level will improve substantially with the right HE furnace.

NREL’s “DEVap” The Future of Cooling!

Picture Courtesy Larry Page

The Dog Days of Summer are on us already and the heat is climbing everyday. It is a tough choice between deciding whether to switch the Air Conditioner on or keep the windows open which would be the green thing to do. When the heat gets unbearable it is difficult to not reach for the thermostat and switch on the Air Conditioner.

Air Conditioners also mean heftier power bills it climbs up in to the 100$ plus range and one is left wondering what to do to keep oneself cool without spending so much energy and money. MIT’s Technology review states it well “When it comes to home comforts, few inventions can beat the air conditioner for its ability to help us tolerate the dog days of summer. The problem is, when it comes to energy-guzzlers, few inventions can beat the air conditioner”.

A soothing solution is on the way! for both our wallets and our homes.The NREL has built on the basic concept of the swamp cooler to make it effective and efficient to solve our cooling issues.

The U.S. Department of Energy’s National Renewable Energy Laboratory has invented a new air conditioning process with the potential of using 50 percent to 90 percent less energy than today’s top-of-the-line units. It uses membranes, evaporative cooling and liquid desiccants in a way that has never been done before in the centuries-old science of removing heat from the air.

What are Evaporative Coolers?

Evaporative coolers or Swamp coolers have been used for many many years all over the world to cool rooms during the dog days of summer. They basically use evaporating water to cool the air around. They are referred to as Swamp coolers in the US probably due to the swamp like smell the algae assocaited with earlier products. Swamp coolers are perfect for areas with high heat and low humidity. In dry, arid climates, the installation and operating cost of a swamp cooler can be much lower than standard conditioning, often by 80% or so. However, swamp cooling and vapor-compression air conditioning are sometimes used in combination to produce optimal cooling results.

Swamp coolers are being used world over in tropical countries as a cheaper alternative to Air-conditioning and are typically referred to as desert coolers. The filters which the hot air passes through is made of hay/other fibrous substances which soak in water and let air pass through. the filters are cleaned in regular intervals to keep it algae free.

Like mentioned earlier the thing to watch out for is humidity which works against the cooler as adding more water to the already humid air just makes it more sticky and not cool.

The Coolerado cooler is a unique cooler which uses indirect evaporative systems use a purge air stream that removes heat from the product or supply air stream that is then directed into a building. This still does not help in humid conditions.

NREL’s DEVap The Future of Cooling!

The DEVap solves that problem. It relies on the desiccants’ capacity to create dry air using heat and evaporative coolers’ capacity to take dry air and make cold air.

“By no means is the concept novel, the idea of combining the two, But no one has been able to come up with a practical and cost-effective way to do it. The idea is to revolutionize cooling, while removing millions of metric tons of carbon from the air,” NREL mechanical engineer Eric Kozubal, co-inventor of the Desiccant-Enhanced eVaporative air conditioner (DEVap), said.

Most people know of Desiccants as the small sachets which come with shoes etc to keep them dry. NREL uses syrupy liquid desiccants – highly concentrated aqueous salt solutions of lithium chloride or calcium chloride. They have a high affinity for water vapor, and can thus create very dry air. Desiccant based cooling systems in use were very complex and hence used only for industrial purposes.

NREL uses thin membranes that simplify the process of integrating air flow, desiccants, and evaporative cooling. This results in an air conditioning system that provides superior comfort and humidity control.

The membranes in the DEVap A/C are hydrophobic i.e. means water tends to bead up rather than soak through the membranes. Imagine rain falling on a freshly waxed car. That property allows the membranes to control the liquid flows within the cooling core. “It’s that property that keeps the water and the desiccant separated from the air stream,” Kozubal said.

Picture Source NREL

NREL senior engineer Eric Kozubal examines a prototype air flow channel of the DEVap air conditioner, which he co-invented. The graph superimposed on the photo shows shows how hot humid air, in red, changes to cool dry air, in blue, as the air passes through the DEVap core.

The Devap A/C’s desiccant and evaporative cooling effect work together to create cold-dry air.

What makes it Green and Wallet friendly?

  • DEVap uses 50 percent to 90 percent less energy than top-of-the-line refrigeration-based air conditioning.
  • DEVap uses salt solutions rather than refrigerants, there are no harmful chlorofluorocarbons (CFCs) or hydrochlorofluorocarbons (HCFCs) to worry about.
  • A standard A/C uses around 13pounds of refrigerant which is equivalent to burning more than 1,300 gallons of gasoline, or driving over 60,000 miles in a 2010 Toyota Prius.
  • Traditional air conditioners use a lot of electricity to run the refrigeration cycle, but DEVap replaces that refrigeration cycle with an absorption cycle that is thermally activated. It can be powered by natural gas or solar energy and uses very little electricity.

When one sees what it can do it means that DEVap could become the most energy efficient way to cool your house irrespective of where you live; Phoenix, New York, or Houston.

NREL has patented the DEVap concept, and Kozubal expects that over the next couple of years he will be working on making the device smaller and simpler and perfecting the heat transfer to make DEVap more cost effective.

Eventually, NREL will license the technology to industry, “We’re never going to be in the air conditioner manufacturing business”, said Ron Judkoff, Principle Program Manager for Building Energy Research at NREL. “But we’d like to work with manufacturers to bring DEVap to market and create a more efficient and environmentally benign air conditioning product.”

Hoping the day comes soon when the DEVap is available as a Green and wallet friendly cooling solution on the market. Live Green!

Sources :

NREL article by Bill Scanlon and the picture.

MIT’s Technology Review where I read it first

The Wikipedia for info on Swamp coolers