Looking back to the “battle of the currents”, Edison and GE v. Tesla and Westinghouse, it can be said that they were both wrong and that it had a huge impact on todays electric technology. Edison contended AC electricity was unsafe and arranged a few marketing schemes to make his point - like electrocuting a rogue circus elephant and convincing New York to use the electric chair for the death penalty. In fact, at relatively low levels AC current represents the unique safety hazard of triggering ventricular fibrillation in humans. A cardiac condition that immediately denies oxygen to the brain and requires prompt, within 90 seconds, Advanced Life Support intervention in the form of a “defibrillator”. On the other hand, Edison’s preferred DC at 110 volts represents both a severe shock and increased fire hazard. Technically, Charles Kettering’s selection of 32 volts DC was a safe choice. Modern safety standards place the safe voltage of DC at 60 volts in dry conditions and 30 volts in wet conditions.
The impact of the dominance of todays AC system is that all of the electrical appliances and devices in our homes are designed to operate on 120 volt, 60 cycle AC power. It is true AC or DC can be used for all of our electric needs - but most of our homes have appliances that operate only on AC. Interestingly, some of our newer appliances convert the 120 volts AC to low voltage DC - computers, printers, electronics, and any device that has a little box in the cord to lower the voltage and change AC to DC. Reintroducing DC appliances into the market is both easy and happening - motor homes and stand alone solar systems are driving demand for 12 and 24 volt appliances and trending to 48 volts DC.
During the 1970’s, inventive minds applied existing electronic technology to allow DC solar panels to be compatible with the AC electric grid. The grid-tie inverter allowed private homes and businesses to install solar panels and produce a portion or all of their electric energy needs. The initial concerns were easily dismissed and the electric companies welcomed the reduction in peak summer and daily demand. As matter of convenience, in most states a fair “net energy” billing scheme where solar energy produced and used or in some cases sent to a neighbor to use was the same value as purchased energy.
More recently, the electric industry has come to fear competition in their monopoly markets and has taken to opposing private homeowner and business investment in solar panels. The Edison Electric Institute (EEI), the electric monopoly industry trade organization, has engaged the American Legislative Exchange Council (ALEC) to develop punitive state legislation for home owners - onerous punitive monthly fees and low value for energy made available to neighbors and billed by the electric monopoly at retail price. It is a futile endeavor that is doomed to fail eventually. Solar energy is available everywhere and a simple axiom that investing in a solar panel to produce your own electric power makes more sense than an electric monopoly charging for the same panel, land to put it on, a substation, distribution lines that lose power, administrative costs, and the profit guaranteed by federal law and set by the state “Public Service Commission”.
Transitioning to the Future
In the meantime, solar investors should insist on fair treatment from regulators, legislators, and their “public” electric monopoly. A grid-tie system under fair terms allows immediate seamless addition of solar panels and a low cost inverter to a home or business - now! The solar panels are comparable with a stand alone system anytime the owner chooses to go grid free. Solar panels are made out of sand and aluminum and are highly recyclable.
Solar energy used to power air conditioning is a very high value opportunity for homes and businesses to invest in. Air conditioning represents 25% of residential, 40% of commercial, and 23% of national energy usage. Solar energy supply and air conditioning demand are coincident with each other while burning fossil fuels to make cool air creates several times as much waste heat to the environment as it does cool air. Solar air conditioning on homes and retail stores is economically superior and would eliminate old, inefficient, dirty, and expensive peaking power plants and totally eliminate the need to build new power plants for the foreseeable future.
The fact of the matter is that every individual homeowner or business would prefer to be totally free of the electric utility monopoly. Customer hostile solar policies will drive the acceptance of hybrid solar power plants with onsite storage capability and no connection to the grid for electric customers. The grid zero or grid free stand alone solar/battery hybrid electric plant is becoming cost competitive with technically superior performance and reliability. Grid free hybrid systems not only makes this possible but with an excellent return on investment over the lifetime of the system.