I've been taken to task for not being sufficiently supportive of the state's greenhouse gas reduction program and expressing only lukewarm enthusiasm for the 640 mw gas-fired power plant proposed for Charles County. I guess I should explain.
The state is so excited they have talked about giving the new plant an exemption from the cap-and-trade system that will provide tradable permits for carbon dioxide emissions in Maryland. Environment Maryland has praised the new plant as being 'less polluting' than coal plants. So how much will the new plant reduce greenhouse gas emissions in Maryland? The short answer is - none.
The reason it will have no effect is that it will not displace any existing plant. The half dozen or so large coal plants that pump out the majority of greenhouse gases in Maryland will continue to operate full throttle because they have a substantial economic advantage in terms of fuel costs and the demand for electricity substantially exceeds the supply. Certainly, when the emission cap goes into place, their costs will increase a bit, but they will pass all of that cost onto the consumer without any problem because they are relatively low cost (and highly profitable) producers.
No, if we are serious about reducing greenhouse gas emissions in Maryland - and we should be, we need to first have an alternate means of generating the electricity now produced by the big coal plants. That means base load plants that can run efficiently 24 hours a day to provide stable, reliable energy to Marylanders. And they have to operate at a cost competitive with current electricity providers. Most Marylanders have already experienced sharp increases in the cost of electricity over the past two years.
Now some might say that we don't need to build new plants, we can just force our own coal plants to close and bring in electricity from somewhere else instead of generating it in Maryland. But we already know that there is insufficient transmission capacity to substantially increase the amount of electricity bought into Maryland from other states. And besides, generating the electricity in Pennsylvania or West Virginia really does nothing to reduce greenhouse gases, does it?
So let's look at the options. There are a variety of fossil fuel types of plants - coal, fuel oil and natural gas. On the renewable energy side there are wind, photovoltaic, solar thermal, wave energy, hydro and biomass. And finally, there's nuclear. Let's take a look at each.
Big coal companies and politicians fro coal-producing states promote something called 'clean coal'. It doesn't exist. The technologies necessary to mine, transport and burn coal for energy without producing harmful pollution or greenhouse gases either don't exist or exist only in the laboratory. The Federal Government, after spending billions of dollars on clean coal technology has essentially given up - terminating all projects.
Several power plants in Maryland use oil as a fuel. Oil is unsuitable for base load plants, however, due to its cost. These plants are mostly used to provide electricity during periods of peak demand. Further, these plants produce significant amounts of greenhouse gases (less than coal, though) and can generate other pollutants.
Natural gas has become a more popular fuel for electricity generation due to it's relative cleanliness (compared to coal and fuel oil) and it's ease of supply. A large gas transmission line runs through Maryland and the LNG terminal at Cove Point feeds additional supplies into the region. Advanced combined-cycle gas turbine installations can reach efficiency levels in excess of 60 percent (i.e. 60 percent of the energy in the fuel is converted into useful output). Natural gas, when used to generate electricity, creates only about half the carbon dioxide per kilowatt compared to coal. The prinicple problem with natural gas is cost - it costs about five times as much as coal per unit of energy (and about half what fuel oil costs). Natural gas prices have been increasing steadily over the past several years, too.
Renewable energy is very popular and for good reason. It doesn't rely on a diminishing source of fuel and it's generally pretty safe. There are limits to each of the technologies, though.
Wind power is one of the more cost effective of the renewable technologies. Substantial improvements have been made in the technology in recent years and it can, in some cases, be quite competitive on a cost basis. The big problem with wind power is, of course, the wind which is notoriously variable. The amount of energy available in wind varies with the cube of the velocity. Studies at the Lee Ranch wind power facility in Colorado have shown that half of all the available energy arrived in just 15% of the time. Thus, for wind energy to be suitable for base load generation, substantial backup generating plants would have to be built. A further problem is that in Maryland, the strongest sustained winds are in the winter while our highest electricity demand is in the summer.
Much has been said and written about photovoltaic energy. The fact is, though, that it is still very costly as a source of base load electricity. Until the technology improves substantially, this isn't an option.
Solar thermal - a technology where sunlight is used to heat a fluid which is then used to drive a turbine or energy to generate electricity. This is an interesting technology which can be quite competitive where conditions are favorable - generally in low latitude deserts - not in Maryland.
Biomass, which includes the use of landfill methane, can efficiently generate electricity and can make a contribution to Maryland's electricity supply. Unfortunately I don't believe there's suffient biomass available in Maryland to make a big dent in our electricity needs.
There's not a lot of available hydropower in Maryland that hasn't already been tapped, although there could be some small-scale hydro installations at some water reservoirs with little cost. The additional amount of electricity would be small. Ocean waves contain considerable energy, but the technology to harness that energy hasn't been perfected.
That leaves nuclear. In my next post, I'll discuss the pros and cons of that.