Natural Gas Promoted As a Wind Backup

7 Comments

1. They don’t want to mention that Natural gas caused 11 deaths and the disaster in the Gulf,never mind the explosions in Connecticut and Pennsylvania that killed additional workers as well.
   Eureka baby….

2. It makes me want to go out and build renewable energy projects to reduce the demand for natural gas burned in ‘dirty’ inefficient gas fired power plants.
   I also want to build new nukes to reduce the amount of NG burned in CCGT.

3. Unless you have plenty of hydro, wind locks gas generation into the system. Every time.

4. Wind only locks gas into the system because nuclear designers have designed existing civilian plants for baseload rather than load-following. Both Rod (on subs) and I (on Nimitz-class A4W plants) have operated nuclear plants that are highly responsive to load changes.

5. NG as backup for Wind & Solar. Pure Spin. What they are actually talking about is replacing cheap baseload Nuclear & Coal with a VERY EXPENSIVE Wind/Solar/NG system. Most of that system energy – 80-90% will come from NG. And the inefficiencies of cycling that NG will use as much extra fuel as the Wind/Solar would have theoretically saved.
   And I thought the #1 goal was to reduce our Economy Destroying Oil Imports, as well as Oil costing 2.7X that of NG per unit of energy. So how does replacing Coal & Nuclear with Wind/Solar/NG reduce Oil Imports?
   It makes much more sense to use that precious NG stored energy to make Methanol. It costs 3.1 cents per liter to produce Methanol from NG. Include the 78% conversion efficiency and current price of NG feedstock and that would be 12 cents per liter or 45 cents per USgal. Methanol burns at double the efficiency of gasoline in a converted diesel engine, and in a series Hybrid you can double that again. So including Methanol’s lower energy density, that would be like paying 23 cents per gal for gasoline – production cost. And much lower emissions. And Methanol -> DME, DME being the best fuel for diesel engines. Higher Cetane number than diesel and much lower emissions.
   And what’s with us folks who don’t have access to NG pipelines being stuck with smelly, smoky Oil home heating? 2.7X the cost of NG heating. So going NG->Methanol for clean-burning home heating would cost 1/3rd that of heating oil. And store it in a cheapo plastic fuel tank that would last for decades. Spills are trivial

   1. dwbd – I understand your technical recommendations, but I am not so sure about your projection of cost to convert natural gas to methanol. Is that the cost of just the conversion without considering the raw material cost? On a per BTU basis, straight natural gas, without any losses from conversion to a liquid, currently costs about 1/3 of the price of distillate fuel depending on location since gas is more expensive to transport than liquid fuel, assuming that both forms of fuel use similar modes of transportation.
      Supporting computations:
      Diesel fuel (and home heating oil) contains about 130,500 BTU per gallon. The current trading price for heating oil on the commodities futures market (http://www.bloomberg.com/markets/commodities/futures/) is $2.09 (on the web page with the table, the notation is USd/gal, which translates to US dollar cents per gallon). That means that at the trading location, heating oil costs about $16 per million BTU versus a current cost (at Henry Hub in southern Louisiana) of $4.98 for natural gas.
      How much natural gas does it take to make a liter of methanol? I do not know where to find that conversion. I also do not know about the statement “methanol burns at double the efficiency of gasoline in a converted diesel engine”. That sounds a little like the kind of statement that Amory Lovins would make. Do you mean that a car getting 20 miles per gallon using gasoline would, all else being equal, get 40 miles per gallon using methanol?
      That cannot be correct since the National Association of Fleet Administrators (NAFA) list of energy equivalents for various fuels indicates that gasoline contains more than twice as much energy per unit volume as methanol does. (Specifically, the standard table lists 114,100 BTU per gallon for gasoline versus 56,800 BTU per gallon for methanol.)
      Cetane or octane may be higher in methanol but you cannot get out more power (energy per unit time) from a lower initial energy input.
      Note – though an Otto cycle engine is slightly less efficient than a Diesel cycle engine due to the higher operating temperatures and pressures in a diesel machine, the big reason that diesel engines generally obtain higher miles per gallon than gas engines in the same vehicle is that diesel fuel contains more energy per unit gallon (130,500 BTU for diesel versus 115,100 BTU for gasoline).
      In my personal circumstance of driving a diesel powered Jetta, I also get improved fuel economy because the power rating of the engine is quite a bit lower than the power rating for the gasoline version. My TDI has just 90 horsepower, so when I put the pedal to the metal to accelerate into traffic, I consume less BTU during acceleration than someone driving a gasoline version of the same car with a 160 HP engine. That works pretty well since the diesel thermodynamic cycle natural has a higher torque at low RPM so my acceleration is acceptable even though I need less top end HP. Due to the higher energy input and lower top end power, I have averaged more than 45 miles per gallon for the past 203,000 miles.

6. Another little point about NG for power production. The biggest new source of conventional NG in Canada is in the Arctic. The pipeline is $17B for1.2 BCF/day or 15.1 GWth. That’s $1.1k per kwth. Projected 14 yr supply of NG. So burnt in a powerplant at an avg 50% efficiency that adds up to $2.2k per kwel to the real capital cost of the plant. Since the Canadian Taxpayers will end up paying for the pipeline, that is a direct added subsidy to the capital cost of an NG powerplant.

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