Our problem is the ever rising costs of non-renewable energy from natural resources and the resulting energy crisis facing our planet. Solar energy is not a revolutionary technology by any means and has long been criticized for it’s inefficiency and other shortcomings. Modern advances by companies such as DayStar Technologies have made great gains towards reducing the power conversion inefficiencies and have succeeded in creating a solar cell foil that is close to 20% efficient as opposed to the traditional 10% and have greatly reduced costs with CIGS technology . Our product addresses the other implementation difficulties related to solar energy, primarily, “What do we do when the sun goes away every night”. We ought to store the energy right? And how do we propose to do that? Well with batteries, of course! But its not that simple, the battery currents and voltages need to be regulated to provide optimum power transfer to the client because efficiency reduces cost and high cost is the last major road block in making solar a feasible energy alternative. The heart of our product then is microprocessor control of the stored energy.
The approach taken by our team of engineers was essentially an embedded systems approach. We needed to interface the microprocessor which we programmed, with some current/voltage limiting hardware, a buck regulator, opto-isolators, and various other necessary components to effectively read the currents coming off the panels and entering the batteries, and those currents leaving the batteries to power some desired application. It’s true our project as described is not breaking any real ground, however, most products meant to regulate a battery voltage are completely analog and offer very little control to the user. They are also not digitally self-optimizing which is a possibility for us. As far as future improvements and evolutionary capability we are offering an extra buck regulator component and a few pins for a future expansion solar array as technologies in this sector improve to generate even more power. We suspect we can be competitively priced, if not cheaper than our closest competitors who don’t offer expansion options and digital flexibility.
1.1 BACKGROUND OF STUDY
Harnessing solar energy has been the holy grail of renewable energy research for some time now. Photovoltaic solar cells convert light energy to high voltage and low current which can be manipulated to provide power to our modern electrical devices and homes. With the ever rising costs of fossil fuels, the need for an efficient and affordable solar energy system has never been greater. This is why our market of interest focuses on the residential community to help offset the cost of utilities while striving to be environmentally conscientious. One group, Energy[R]evolution claims, “The sunlight which reaches the earth’s surface is enough to provide 2,850 times as much energy as we can currently use. On a global average, each square meter of land is exposed to enough sunlight to produce 1,700 kWh of power every year.” These are encouraging statistics when coupled with advances in our field, including the
conversion efficiency of the solar cells, with companies like Day Star Technologies and ENREL developing a solar foil which is nearly 20% efficient up from 10% in the previous generation . However, the energy from this foil would be useless if it could not be stored in some manner for use at another time when the sun may not be as readily available (i.e. batteries). The field of solar energy engineering requires products like ours to maximize this power storage and monitor the power levels.
Our project is essentially all of the technology that must be in place in order to interface the power-generating solar cells to the power-storing batteries. In order to accomplish this we must choose a microprocessor, generate its necessary control signals, read in the voltages and currents coming off both the batteries and panels, and use a buck regulator to manipulate the voltages and currents according to an optimization scheme
regulated by the microprocessor.
With the guidance of our industry expert, Jack Gilmore, we plan to demonstrate this controller, at scaled down operating levels, at Engineering Days in the spring of 2007. We intend to have this project demonstrated outside with bona fide solar panels and not simulated ones. Although this is what we plan to accomplish for the end of the year the overall goal for this assignment is to implement this technology into a household
1.2 STATEMENT OF PROBLEM
Improving solar lead acid battery charger has been a major problem, that is why this research has been carried out. Several research has been done on this regard but to this effect, improvement is always allowed.
1.3 AIM / OBJECTIVE
The design work deals with solar powered lead acid battery charger. Working on this project requires some software application and the type of microprocessor we chose.
1.4 THE SIGNIFICANCE OF THE STUDY
The significance of this great design project is aimed at helping the students to carryout design projects, understand how solar lead acid battery charger works. It will also assist the lecturers and students to research work and design analysis. It helps also the society at large to be aware of the jeopardy of poor design of solar power lead acid battery charger
1.5 SCOPE OF WORK AND LIMITATION
This research involves the design of a solar lead acid battery charger which can be achieved to recharge works and designing of some components. This can also be achieved through some software