Design and Realization of a 300 W Human Power Energy Generator System on a Bicycle

In this study, we discuss a new type of human power energy generator (HPEG) system that has been designed to work with bicycles. To analyze the magnetic circuit, the finite element analysis was used to simulate the magnetic flux density in the axial flux permanent magnet(AFPM)generator. The performance of the designed HPEG was tested by mounting the E-bike in the training stand and pedaling at different speeds. Based on the experiments, the maximum output of current and voltage were 1.4 A and 215 V, respectively. The output power of the developed HPEG system had the maximum output power 300 W at the rotation speed of 790 rpm. On the road, the HPEG system is able to generate excess power to recharge the battery while pedaling, braking and coasting downhill, which turns the extra momentum into electricity to charge the battery. When the speed of the bike is above 25 km/hr, it is easy to generate approximately 100 watts of power by pedaling. It can provide a 10% increase in range. Furthermore, the developed HPEG system can also provide a method of generating electricity by means of a modified exercise bike for use in energy storage. Energy stored in battery form can act as a supplemental energy source for battery banks that may already be used for household appliances.


Introduction
Access to inexpensive energy in useful forms has been one of the most important issues for mankind throughout history.The fear of forthcoming energy shortages has even been the cause of wars.Recently, there has been the introduction of renewable energy, such as small hydro, wind, solar, geothermal, and biofuel energy.The most interesting of these energies are wind power and solar energy.However, the use of solar energy technologies has a shortcoming of very high cost.The limited life of solar panels is about 10-20 years and the production requires the use of a large amount of silicon, germanium, and boron, which may cause pollution in other areas (Nelson, 2003).On the other hand, the wind power energy has high installation cost, big noise, locations and wind farm requirements (Lei et al., 2005;Bansal et al., 2002).Due to various factors mentioned above, there is low interest in renewable energy investment in the private sector.Therefore, the use of renewable energy tends to be limited to government and education and is not prevalent in the public.When selecting a suitable renewable generator, consumers focus on low cost, easy installation, minimal limitation due to topography, height and size, realizable and low maintenance rather than the volume of electricity generated.Hence, bicycles become one of the best choices.Because of their mobility and convenience, bicycles turn out to be a useful tool for people traveling in the city.Moreover, bicycles do not require fossil fuel or generate any air pollution or noise.By combining bicycles and generators, the public would be able to recycle the long ignored human energy, significantly decreasing electricity bills and better protecting the environment.Therefore, it is generally recognized that there is a need for new methods of affordable, non-polluting personal generator.In this paper we provide the most primitive clean energy that has been used for thousands years -human power energy.Human power energy is also more abundant and less dependent on environmental conditions, such as climate, than solar energy and alternative sources of energy.
It is obvious that the bicycle is a well-understood and often used machine, but the electrical versions have had little commercial success over the past century.In the past, some types of bicycle generators have been developed, such as drum generators, sidewall generators, and hub generators.Sidewall generator is the most

Results
The system the techno conducted mounting energy-pre Figure 4  The output power of the developed HPEG in parallel configuration is illustrated in Figure 5.As shown in Figure 5, the developed HPEG had the maximum output power 300 W at the rotation speed of 790 rpm.We also found that at the normal speed 500 rpm (corresponds to downhill speed 60 km/hr) it is easy to achieve 215 W, even if in road travel at 200 rpm (about 25~30 km/hr), it can also achieve 100 W.
Figure 5.The output power of the developed HPEG Furthermore, the developed HPEG system can also provide a method of generating electricity by means of a modified exercise bike for use in energy storage and running household appliances.The output alternating current (AC) is converted into a direct current (DC) by battery charger.The energy can be stored in various types of lead-acid batteries.Energy stored in battery form can act as a supplemental energy source for battery banks that may already be used for household appliances.If AC appliances are in place then an inverter must be used to transfer the 12 volts of DC current into the standard 110 volts of AC current for usage by these appliances.Appliances that could be powered include radios, televisions, lights, power tools and other appliances that pull relatively low amounts of energy for their usage.
In order to increase the driving range, we can install the HPEG system on the hub of the rear wheel of the electric bicycle, which can create excessive power to recharge the battery while pedaling, braking and coasting on a downhill.In this work, the Lithium battery was adopted for its light weight and long duration power.The power system consisted of a battery (36 V, 9 Ah) and an electric brushless DC motor (350 W). Figure 6 illustrates schematically the prototype of the electric bicycle with HPEG system.The system can transfer the kinetic energy to electric power and recharge the battery by use of a planetary AFPM generator, which can extend the range by 10-20 miles.
Figure 6.The prototype of the designed electric bicycle The daily and hourly energy demand has been calculated.It is possible to calculate the rate of recharge that is needed to replenish the battery.We are examining the system with a 12 volt, 100 Ah battery.It would take 6 hours of pedaling to full charge the battery by mounting the bike in the training stand and pedaling at speed of 400 rpm.Though the time needed to generate electricity seems too long for one person to put out, it would probably be most appropriate for households with multiple people.Table 1 lists the appliances that the full charge battery could be powered.Currently the average installation cost is 10,000 US dollars for a 1,000 watt solar panel.Moreover, the amount of hours that the solar panel can generate electricity depends on the amount of sunlight received.The majority of small wind mills are installed by the government and education, not residential, due to unstable wind power, 6 meters distance requirement and limited space.Compared to solar panels or wind mills, HPEG is more convenient because it can be installed on bicycles.The cost of HPEG is approximately 300 US dollars and could be lower once it can be mass-produced.Therefore, HPEG is cheaper than other renewable energy devices.

Summary
The purpose of the paper is to introduce an electric generator, which easily recycles kinetic energy, allowing the public to conserve energy and reduce carbon consumption.In this study, the prototype of the HPEG was designed, fabricated and tested under different rotational speeds and wire configuration.Human power is a readily available source of renewable energy.It is user-friendly, portable, and available whenever you need it.
The power output of the designed HPEG was directly proportional to the effort of the person pedaling.Experiments showed that the maximum output power of the developed HPEG could achieve 300 W at the speed of 790 rpm and 100 W at the normal speed of 25~30 km/h during road test.It can be also employed as an emergency power generation and battery charging for household appliances and exercise systems that do useful work generating power while exercising.The prototyped generator is relatively small and cheap.The information gained with current experience can be employed as a useful guidance for further developments on this technology. Figu

Table 1 .
The appliances that the full charge battery could be powered