posted Mar. 28, 2010
Natural Gas and Alternative Energy: A Promising Combination
Possible benefits include drought-protected electricity for Seattle
by Martin Nix
Natural gas is used to heat homes and to generate much of the nation's electricity. It's a very effective fuel, and there's no shortage of it domestically. It can even be made from urban compost and forest residues.
Another benefit of natural gas is that it is "clean burning," at least in comparison with most other fuels. The emissions from Natural Gas are basically half water vapor and half CO2, with practically no other pollutants. The CO2 emissions can be greatly reduced by integrating alternative energy technology.
A program of installing solar hot water heating systems would drastically reduce the amount of natural gas burned directly in homes or indirectly in electrical generation plants. Solar hot water systems use evacuated-tube solar collectors to supplement a gas or electric water heater. These solar collectors work even in cold, cloudy conditions, and are nearly 90% efficient. By cutting back on the amount of gas burned in homes, there is a reduction of CO2 emissions.
Conserving gas in this way also helps to keep line pressure up in the pipeline. Part of the problem with natural gas distribution is pipe diameter size. Pipes can only haul so much natural gas. In the winter, when the natural gas utility is overloaded, it can cause a drop in line pressure. Solar hot water systems help relieve the overload. This lessens the need for gas infrastructure improvements.
Wind energy can also be used in the winter to make hot water and building heat. Often wind energy is more available in the winter, exactly when solar isn't. Wind energy can also be harnessed to produce hydrogen from water electrolysis. The hydrogen can then be used to enrich organic sources of natural gas, increasing the potency of the gas.
Another way to reduce consumption of gas is to have an aggressive greenhouse and window-replacement program. Some homes now have four panes of glass, instead of just one or two. This reduces the amount of heat escaping. It also has another bonus: the home is quieter from outside noise.
Greenhouses can be as small as a south-facing window. Solar greenhouses not only provide fresh air from plants, but also help heat a home and reduce the grocery bill.
By conserving natural gas in homes, supplies are increased for two additional natural gas markets: compressed natural gas (CNG) cars and cogeneration.
CNG transportation is a growing market. Natural gas for cars is going to become more popular, especially as the price of oil increases.
Cogeneration is a system that uses natural gas not only to generate electricity on-site, but also to heat or cool the site. Equipment can be retrofited to existing commercial buildings, like laundrymats, which have a constant high demand for hot water. Grocery stores have a constant energy demand for air conditioning, especially in the summer. The heat from a natural gas electrical generator is recaptured to drive a hot water boiler or an absorption-cycle air conditioner. This makes natural gas more efficient, in that it uses the same amount of energy to make both heat and electricity. Electricity is almost like a free bonus.
Still, any use of natural gas is going to emit CO2. One of my favorite suggestions to mitigate this is to plant more trees in parking lots. Another trick is to tap into the rich underground salt water formations underneath deserts. By using solar pumps and wind pumps, deep underground water can be pumped to the surface, to create evaporation ponds. The sun evaporates the water, which creates more local rainfall, fog and dew. This increases the amount of vegetation, which again removes more CO2. Salt water plants like algae can also be grown directly in such ponds.
The fact is that a combination of simple alternative energy technology and natural gas can open up supplies for cogeneration and CNG vehicles, which in turn can replace the demand for far more polluting fuels such as coal and gasoline.
In order to translate some of the above ideas into practical business, here's an example of what could be done in my city, Seattle.
Currently, the Seattle City Light (SCL) electric utility has an investment portfolio in wind energy and renewables, but not for a combination of solar and natural gas as I've described above.
In the Spring and Summer, SCL's hydrodams normally produce more electricity than we need. But during drought years and during the winter, SCL has to buy electricity from thermal sources, mostly from natural gas generators of private companies.
If Seattle City Light were to purchase the natural gas utility owned by Puget Sound Energy (a subsidiary of Translata of Canada), it could convert that gas utility to be solar-efficient.
SCL is known for its innovation, so it could be a prime mover for residential solar hot water, greenhouses, quadruple-glazed windows, and cogeneration.
Natural gas cogeneration could drought-protect Seattle in a high-efficiency way.
Basically, the whole city could become a solar power plant, and by combining this with natural gas, it would make SCL into a very self-reliant utility. The utility could then sell surplus electricity to other utilities, at a profit. At times, Seattle ratepayers might not even have to pay for electricity, but get paid instead!
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