Happy Hopping Solar Powered Frog

Build a hopping solar powered frog. He’s adorable for one thing. Why else? The best part… this easy-to-use science kit teaches adults and kids all about solar power in a fun science experiment kit designed right. Demonstrate that with solar panels for energy, no batteries are required - truly! This funny little amphibian draws applause. Amphibian lovers everywhere can’t stop watching the little guy hop. No matter how old you are, hopping feet and googly eyes are hard to resist. Mini solar powered robot kit is fun to build and entertaining to play with A build-it-yourself educational solar hobby kit Hind legs and rubber feet hippity-hop in the sun or very close to a non-florescent light bulb Includes 20+ pieces and picture instructions for easy assembly An alternative energy science kit, perfect for the first time experimenter with little or no experience Ages 10+

Customer Review: fun jumper

The frog has some assembly when it arrives, but it is very cute and jumps. It seems sturdy enough to last a while. It turns when it jumps and looses the light so it stops quickly to need adjusting to the sunlight. Both the 4 and 7 year old boys enjoy playing with it.

Customer Review: Frog won’t hop

I recently purchased this kit. The instructions were clear enough and assembly wasn’t overly difficult, but I found that after it was assembled it wouldn’t work. The frog is supposed to work by having the solar-powered motor wind up (and release) its spring-driven rear legs. The motor works OK, as do the gears that go between the motor and the cam that winds up the legs. Unfortunately, however, the gears are connected to the cam by a smooth round rod, and the friction between that rod and the cam isn’t enough to move the legs - the rod rotates, but the cam doesn’t move. I tried to fix this by putting a drop of superglue in the cam and then reattaching it to the rod, but must have used a little too much, gluing the cam to the body. The rear legs rotate on a hexagonal rod that prevents the sort of slippage I described - it’s too bad they didn’t do something similar for connecting the gears to the cam.

Anyway, I wouldn’t recommend this kit to anyone. I did get a small solar cell and pager motor out of it that should be usable for some other project, but still resent that I was suckered into paying for a piece of junk like this kit. I’m honestly curious whether anyone has ever gotten it to work.

Solar collector systems

Although solar collectors are less well known than photovoltaic solar cells, they are a very effective method of providing space heating and/or hot water for domestic properties. This is an important factor when considering energy efficient housing as water and space heating are usually the largest single consumer of energy in domestic households. These systems work by directly capturing the sun’s energy and converting it into a more usable form (heat). Most parts of the world have abundant solar energy available (averaging about 1000 watts per square meter in clear conditions).

Solar collector systems consist of the collector itself (usually roof mounted) along with a heat transfer circuit using fluid such as water/glycol, a pump or other method of circulating the the fluid and in some systems a heat exchanger. Heat from the collector is transferred to a reservoir (such as a well insulated hot water cylinder) where the heat can be utilised by providing hot water for heating (using radiators or underfloor heating) and/or hot water for showers and bathing in a domestic environment. Commercial uses include warming swimming pools, heating industrial dryers and various manufacturing processes requiring heat.

There are two main types of solar collector heating systems, thermosyphon systems and pumped systems.

In the thermosyphon system, the storage tank for the fluid has to be placed above the collector as there is no pump in these systems. Water in the collector rises as it is heated naturally circulating around the tank. This system is requires no moving parts or external energy but placing the tank higher than the collectors is not always physically possible.

A pumped system uses a pump to circulate the water, so the tank does not have to be located above the collector. The disadvantage of this system is that it requires external energy to run the pump and an electronics system to control the pump properly.

Both the pumped and thermosyphon type systems can be further divided into three distinct types of collector systems

Flat plate collector - consists of a thin, thermally stable absorber sheet with the tubing containing fluid arranged in a coil or grid pattern underneath encased in a glass or polycarbonate cover.

Parabolic trough concentrating collector - This type of collector uses a trough-shaped parabolic reflector to concentrate sunlight on a pipe or tubing which contains the coolant which is used to transfer the heat. There are large scale versions of these types of systems in use today in the form of solar towers surrounded by parabolic mirror reflectors which track the sun (heliostats) constantly focussing the energy on the tower.

Evacuated tube - similar to the flat plate collector but using multiple vacuum tubes to reduce convection heat losses. This type of collector is especially useful in milder climates where it can reach much higher temperatures than a conventional collector.

Home solar systems

When you mention alternative energy most people immediately think of solar power in its many forms. Solar energy can actually be utilised in a number of ways. First of all lets deal with the semantics, technically every form of energy is derived from solar, but in this article we will be discussing direct harnessing of solar radiation for energy.

There are several applications of solar energy collection currently being used. From space heating to cooling, water heating to generating electricity. Electricity generation is currently the most popular in domestic installations using photovoltaic cells. The production of Photovoltaic cells has been doubling every two years making this the fastest growing form of energy technology.

How do photovoltaic cells generate electricity?

In simple terms, photons from sunlight agitate electrons in a photodiode creating electricity. Solar
photovoltaic cells produce direct current (DC) electricity from light, this can be used to power DC
equipment, to recharge a battery or using an inverter (converting the DC to AC) to power household
appliances. The photodiodes used in solar cells need protection from the elements and are usually covered with a transparent glass or plastic sheet.

The efficiency of solar cells has been steadily improving in recent years, from an avaerage efficiency of 15% in 2006 we are already seeing cells commercially available with an efficiency ration of 23% and many research and development projects are under way (many using nanotechnology) with confident projections of over 42% efficiency.

Economies of scale, in conjunction with technological advancements, has meant that solar cells are now affordable and economically viable for domestic use in many parts of the world. Thousands of people are already harnessing solar energy to power their homes. In addition to eliminating/reducing their electrical bills many people enjoy increased feelings of security knowing that their energy supply will not run out any time soon and is environmentally friendly. The only cost’s with home solar systems are the one-off installation costs. Large solar arrays for commercial systems can cost tens of thousands of dollars. However, there are step-by-step guides showing you can now build your own solar cell system powering your home for less than $200, using components readily available from hardware store.

The pick of these DIY solar guides by far, is the one produced by Michael Harvey. Michael’s complete step-by-step fully illustrated manual and easy to follow videos will have you generating your own electricity for less than $200, reducing your power bill by 80% or even eliminating it completely!