ELECTRICAL ENGINEERING

   If you have an electrical engineering project, and you are looking for someone to assist you in making the project a reality, then contact us with your project plans today.  ICS guarantees the secrecy of your project and plans, and can provide contracts specifying the terms of your project.

   We specialize in electrical engineering where wired, or "smart" houses are involved.  At times, certain systems can be retro-fitted into existing homes, but we can produce some really amazing results when we can work with a new home just going up.  We deal in low-voltage, high-current solar power grids, secondary power generation, specialty lighting, custom in-home audio/video systems, not just home theaters, satellite signals, home automation, natural or "free energy" type heating and cooling systems, and much more.

   This diagram is a little too detailed to be read easily from within a web page -- it just can't do it justice, however the emergency generator is visible in the lower left of the diagram.  Mounted to the side of the garage wall is a secondary load panel designed for carrying 12 vdc at approximately 500A, and a cutover switching panel to switch between AC and DC power.  In DC power mode, the houses primary wiring system is carrying the 12 vdc, which is being provided by a stack of 12 volt, deep-cycle marine batteries.  The wiring carries DC current at various current capacities, depending upon the intended load.  For a typical duplex outlet, to be used primarily for lighting, and low power devices, such as VCRs, DVD players, radios, and so on, a minimum of 150 watts of 120 vac would be necessary.  The duplex outlet would be powered via a 12 vdc to 120 vac power inverter.

   To generate 150 watts of 120 vac, from a 12 vdc source, we would require 12.5 a of current.  This can be easily calculated, using Ohm's Law:  P = E * I, where E represents voltage, I represents current and P represents total power.  If E = 120 vac, and P = 150 watts, then, by applying the formula thus:  P / E = I, we can determine our current requirement.  For our little example, it is 1.25 a.  Taking these numbers, we transpose our figures to calculate the current requirement of our inverters to maintain the same wattage output, thus:  E = 12 vdc, P = 150 watts, therefore, I = P / E, or I = 150 / 12 = 12.5 a.  In this example, we would need 12.5 a of 12 vdc to power our inverter at the 150 watt level.  If you draw less than the full 150 watts available, the current drain would be proportionally lower.

   All this talk about volts, amperes, power and wattage is all well and good, but to what end?  Well, the idea is to become as self sufficient as you can when it comes to your electrical usage.  ICS  Engineering is very fortunate in that we are in Sunny Arizona -- The home of Solar Power.  Anyway, here is the big, big picture.  The house is roofed with high-efficiency solar cells.  The "solar roof", when in full sunlight is capable of generating 21 vdc at over 400 amps.  (A 1-square foot high-efficiency solar cell generates 0.5 vdc at 3.0 amps!  A matrix array can generate 21vdc at 400 A.  The solar cells charge a bank of 12v lead-acid batteries.

   The longest lasting under extreme discharge situations are the deep-cycle marine batteries.  They are used to power quiet, electric trolling motors with 1 HP or more.  These motors can discharge a standard lead-acid battery into sulphation -- it ceases to hold a charge.  Marine batteries are constructed so as to eliminate this side effect.  The number of batteries required can be calculated versus the amount of wattage required, versus amount of time power is needed.  Obviously, your alarm clock always needs to be powered.  When you run out of battery power, it is wise to have a backup generator running, until the sun ( or the backup generator) can recharge your batteries.

   So, we have a solar "roof", and a stack of marine lead-acid batteries.  How do we distribute 120 vac around the house?  Well, that's a good question -- and the one that we will focus on, now that we have a little background on our theoretical project.  We place the batteries and backup generator in a strategic spot, perhaps in a small prefab utility shed.  The solar cells charge the bank of lead-acid batteries through the use of a specific type of energy controller/regulator that charges and maintains the charged batteries properly, for long life.  Then, the DC current is distributed by a secondary set of extremely high-current, large gauge wiring to a bank of DC-to-AC power inverters.  Inverters of appropriate power are installed for each of the breakers in the panel.  Special 240 vac inverters are wired to heavier electrical loads, although the water heater, kitchen stove with oven, and the clothes dryer should be powered with an alternate fuel such as LP or Natural gas.  Heating should also be done with an alternative fuel.  All of these can be augmented with the use of solar heating panels, whose primary function is not to generate electricity, but to heat water.  Installation of several jacketed water tanks will hold the water for heating and other uses until it is needed.

  So now we have the following systems up and running:

• Solar roof is producing 21vdc at 400a to a solar battery charger/regulator.

• The regulator is charging the bank of batteries from dead to full using 1 day or less of sunlight.

• The batteries are powering two DC-to-AC inverters.

• The backup generator switches in and takes over when batteries are discharged.

 The inverters are apportioned as follows:

• Two 150 watt inverters (2 duplex outlets) per bedroom.  Total DC current:  2.50 a at 12 vdc.

• Two 150 watt inverters for the garage.  Total DC current:  2.50 a at 12 vdc. 

• Two 150 watt inverters for outside lighting.  Total DC current:  2.50 a at 12 vdc.

• One 1,200 watt inverter per bathroom for curling irons and hair dryers.  Total DC current:  120 a at 12 vdc.

• Two 1,200 watt inverters for the kitchen for appliances.  Total DC current: 240 a at 12 vdc.

• Total DC current required for a three bedroom house:  (2.50 x 5) + (120 x 3) = 372.5 a at 12 vdc.

  And, there you have it!  A house that is capable of running on it's own generated power!  Of course, if you produce more energy than you need, your local utility is obligated by law to buy it from you!  They will provide the necessary interface equipment in order to deliver your surplus generated power to the city power utility!  Of course, we can make it even more fun by adding sensors and computer control equipment, and more, to improve efficiency, minimize down times, and replacement costs and frequency of replacement of batteries and other equipment failures.  Advance notice of a failure are possible with additional sensors and planning.  It can be tied into heating and cooling, as well as television, radio, satellite, HD TV and whatever else you've got going on!