Tag Archives: Renewable Energy

Trombe Wall to Heat and Cool Buildings Using Renewable Energy

Researchers at Lund University, Sweden have devised a technique for using an adaptation of the nineteenth century Trombe wall for heating and cooling modern buildings. The modified structure is capable of reducing carbon emissions associated with the heating and cooling processes, as well. Residents of Saint Catherine in Egypt are trying out the invention.

Trombe wall basics

A Trombe wall was a popular method used in the nineteenth century to keep buildings cool during the day and warm at night. The construction was simple, consisting of a very thick wall painted black on the outside surface and with a glass pane in front of it. The black surface, being a good absorber allowed the wall to absorb heat from the sun’s rays falling on it. The glass surface, being a bad radiator trapped the heat for some time. However, as the temperature dropped during the night, the heat was released slowly, keeping the building warm for several hours. Homes and buildings in the northern hemisphere had a south facing wall, while those in the southern hemisphere, a north-facing one.

An additional advantage of this structure is that the glass sheet causes the release of infrared rays. The warmth produced by these rays is more agreeable than the heat generated by traditional convection methods.

Marwa Dabaieh, an architectural scientist at the university has tried out the modern version of the Trombe wall in Egypt where 94% of the energy used is derived from fossil fuels. She explains that the innovation could help reduce dependence on electricity and cut down carbon emissions.

Cost effective production

The researchers have taken care to retain the basic construction methods. The old but popular passive technique has been employed, meaning there are no mechanical parts involved. This makes for an economical operation. The materials that are used are easily available. Wood and locally quarried stone are used for the basic construction, while wool is used for insulation. The glass used is produced locally, too.

Ventilation system

The modified version relies solely on naturally available solar energy and prevailing wind currents in the region. This makes for a very cost effective design structure.

Dabaieh reveals that the new design employs the concept of ventilation to utilize the air streams to generate cooling techniques. This is a major improvement upon the older version of the Trombe wall, which often caused over heating inside the building. The researchers are continually adjusting the vent structures and positions to make the temperature more endurable. This eliminates the need for air conditioning in the hot summer months.

Roping in the locals

Dabaieh reveals that the project has engaged local residents in the construction and installation process. This will help cut down costs further and provide employment opportunities for young people. Since many homeowners in St Catherine who have put up the Trombe wall, have expressed their satisfaction about the structure, several other residents are keen on installing it.

The adapted Trombe wall is a cheap and efficient system that could serve to meet the challenges posed by rising energy requirements worldwide.

How about a solar energy bikini for this summer?

We thought we’d seen just about everything powered by solar panels or solar film until we came across this bikini. Made by Solarcoterie, this bathing suit is made of photovoltaic film strips sewn together in series with conductive thread! With a USB connection, you could be laying on the beach and powering your iPod at the same time. The suit is constructed of 1″ x 4″ solar strips which terminate in a 5V regulator and a female USB connector – perfect for powering your iPod.

The downside is that the bathing suit is a currently custom made offering only so this is not something readily available at your local store. And, we don’t have the power specs but wonder if this also wouldn’t be a great solution for charging other small appliances needed at the beach – like most smartphones and iPads. Of course, this got us thinking about our dream ideas of powering a small cooler (imagine never needing ice at the beach!) or a small fan for cooling off while you’re baking in the sun. The biggest item on our wishlist is always a blender but we’ve got that covered with our battery operated one!

No matter what, we think this use of solar technology is genius.

IKEA completes solar installation in Tempe; 8 more planned

Yesterday, IKEA announced it had flipped the switch on newly installed dual rooftop solar units at its Tempe, Arizona store. The new system is one of the largest solar systems in the Phoenix area and the third such solar energy system for the Swedish home furnishings retailer; they have similar units already in place in Brooklyn, NY and Pittsburgh, PA.

The 300 kW solar energy system will generate 960,000 kWh of electricity annually from 2600 solar panels. It is the equivalent of reducing at least 760 tons of (C02) – which equals the emissions of 133 cars or powering 84 homes annually.

IKEA has other renewable energy initiatives in place. Already operating is solar water heating in stores in Charlotte, N.C.; Draper, Utah; Orlando, Florida; and Tampa, Florida. In addition, a geothermal system is being installed in a store under construction in Centennial, Colorado.

It was also announced that eight California locations are on deck for solar systems. In all, IKEA will be installing nearly 20,000 solar panels at eight of its California locations. IKEA expects the panels to generate 6.65 million kilowatt hours of electricity annually which is enough to power 580 homes for a year. Pending governmental approval, it will begin installing the renewable energy systems later this fall at existing stores in East Palo Alto, Emeryville, West Sacramento, Burbank, Costa Mesa, Covina and San Diego along with its large distribution center in Tejon.

The future of solar power: Flexible solar panels

As the popularity of solar energy grows, so does the selection of solar equipment that is made available. The big trend in solar energy right now is flexible panels.

Flexible solar panels have many advantages over traditional framed solar panels. The flexible solar panels are lightweight so there is less worry in the installation process and during use. They can also be installed on a semi-permanent basis because they are very easy to remove and install elsewhere.

Probably the biggest advantage is that they can be manufactured in any size or shape so they can be used in unconventional places.

In the past, the biggest disadvantage of the flexible solar panels is that they could only power low-wattage devices however that has changed significantly in the past year as new solar technology has been introduced. The newest flexible panels that are available for commercial applications have the ability to collect more energy than earlier versions.

In the future, we will be seeing even more advances in solar energy products based on this emerging technology.

Are deep water floating wind turbines on the horizon?

Think of the possibilities of having deep water floating wind turbines to generate energy. Are they feasible? According the Journal of Renewable and Sustainable Energy, the answer is ‘yes’.

Engineers from the Marine Innovation and Technology have demonstrated that their buoyant, triangular platform which is called the WindFloat, could support a 5-megawatt wind turbine. They have conducted studies to determine whether the platform would stay erect. The platform was anchored to the ocean floor (at 164ft of depth), balanced with horizontal plates and a ballast system to counteract the motion of the ocean. The end result? The prototype did not topple.

That is good news for many. There are other similar projects in the works, but the possibility to see a 150 megawatt floating wind farm based on the WindFloat technology is now a distinct possibility. The projected date of installation is in 2012.

Turn your old PC fans into mini wind generators

pc fanHere’s a great project that you can do either to experiment with wind turbines or to generate some energy! While the amount of energy produced is not overwhelming, this project can sure get your brain moving in the right direction.

The best thing about this project is that you probably already have everything you need lying around:

  • Thick plastic bottle
  • Old PC fan, bigger the better!
  • A few feet of small wire
  • A piece of wood about 1.5″ square and around 20cm long
  • Two lengths of steel tubing that slide inside of each other, about 1/2″
  • 6 Schottkey diodes
  • Epoxy
  • Super Glue
  • Zip ties
  • An old CD

You can find the full instructions including video here: http://www.instructables.com/id/Upcycle-your-old-PC-fans-into-mini-wind-generators/

If you want to have a kid-friendly wind turbine kit that already has all the pieces you need, we sell one of those. Our kits come with full instructions and all the materials needed to try your hand at creating a source of renewable energy – a wind turbine. The kit also comes with different experiments you can try with your wind turbine once it’s assembled. Great project for summer for the kids!

What is a wind turbine?

A wind turbine is a rotary device that draws energy from the wind. This is different from a windmill, which draws energy from the wind but that energy is directly converted into mechanical energy used by some sort of machinery. Wind turbines are converted into raw electricity.

There are two main types, horizontal and vertical axis, of which the horizontal axis is more common. What are the differences between these two? Horizontal-axis turbines have the main rotor shaft and generator at the top of the tower. Horizontal axes must be pointed into the wind in order for them to work properly. However, the structure of the blades facing the wind also gives them a great angle of attack, which is the angle at which they have contact with the wind. This insures that the blades will be very efficient when converting wind to energy. Vertical-axis turbines are basically the same, except the axis is vertical, and they have the advantage of not having to face the wind.

Wind turbines are made up of three main components, the rotor component, generator component, and structural support component. The rotor component makes up about 20% of the cost, and consists of the blades. The generator component makes up 34% of the cost, and consists of the electrical generator, the control electronics, and usually a gearbox component for converting the low speed incoming rotation to high speed rotation which is better for generating electricity. Finally the structural support component makes up about 15% of the cost and consists of tower and rotor yaw mechanism.

Installing wind turbines can be a great way to save money on your electrical bills and create your own energy. They can be bought pretty inexpensively or you can even build your own and get the supplies to do it for even cheaper. If you are interested in building a basic wind turbine to see how it works, you should buy an educational wind turbine kit to get you started.