Power and Electricity

I have been reading a lot lately about renewable energy sources. Right now there are several things to consider. So let's split things up a bit so we can chew and digest each piece and look at the big picture at the end.

Current power plants produce the following: electricity, low pressure steam, waste. Doesn't matter what type the power plant is, these three are the products.

Waste can take several forms: toxic/nuclear waste, pollutants, heat loss. Obviously we want to reduce these things to negligible amounts, but not always easy. This changes depending on the power plant, fuel, etc.

Low pressure steam (LPS) is generated for several uses. Near cities, it is used to heat and cool office buildings. Within the power plant it is used to help pre-heat water or super-heat steam for steam-power-turbines. There are many uses for the LPS, and if we keep it inside of relatively closed system we can use it for many useful things. Loss of this product is not very detrimental to the applications it is used for, but is good for auxiliary benefits. LPS is not the reason we have power plants, it's just a useful by-product.

Electricity is the main reason we have power plants, and the reason is because it can be used for anything. The problem with electricity and LPS is there is no way to store it reliably without using energy to convert it to a storable format. Batteries cost money and chemicals are toxic. There is the idea that you can pump water up a dam to store electricity, but that costs more energy than it would produce when converted to hydro-electric. Also there is the problem of the environmental effects of a dam/lake, and the fact that you need the proper terrain for supporting a dam/lake for hydro-electric.

Renewable Electricity
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So there are various renewable sources of energy: hydro, geo-thermal, wind, solar, etc. Each has benefits and problems.

Hydro-electricity is generated by dams, produces near zero pollution. Dams can only be built in specific locations and is not suitable for all terrain. Dams also have to maintain a specific water level (head) for proper power generation and for other environmental reasons. Droughts are a problem. Power generation is constant most of the time, but not 100% reliable. We can use dams for power storage by pumping water in the reverse direction.

Geo-thermal energy is generated from heat that is found deep below the earth's crust. Usually water is pumped down to the heat, and is converted to steam which powers generators at the surface. There is minimal pollution and some of the steam can be used as LPS. As far as I know, this is a pretty reliable source of energy. The downside is location is very specific and the start up costs are high.

Wind electricity from wind turbines are relatively cheap, but noisy and require areas where wind is prevalent from a specific direction. The problem with wind power is that it is not constant. What happens when the power dies out? What about the electricity generated at night when there is excess supply of electricity being generated? Let's store it, we'll explain later.

Solar electricity similar to wind power, is not steady nor predictable due to weather. It's also not cheap, but at least it is much less noisy. The time when the energy is being produced it will most likely be used immediately. It will most likely be auxiliary type of power which removes the load of other power producers.

Storing Electricity
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So there are many ways we can store energy. Some are simple: moving water back up a dam. Others are more complicated: batteries. Using a combination of many of these we should be able to more. There is one more which hasn't been discussed much.

Creating liquid nitrogen or other gases into liquid form requires large amounts of energy. The process of creating liquid nitrogen is fairly simple with repeating steps.

Liquid nitrogen is created by compressing air. This causes the gases to release heat. Using cooling coils, we remove as much heat we can. This cannot be done in one step though cause the pressure and cooling required is large. So what happens is the air is allowed to expand a little bit, which causes it to absorb heat (cooling effect). Like when you use compressed air cans they get cooler. Well we use this cooling effect cool some more compressed air with the cooling coils. Repeat this process and you will have water drop out first, then some other gases like CO2 and eventually nitrogen will become liquid.

Now all that energy we have left over from wind at night or power not being used could be used to make liquid nitrogen. In the winter we can use some of the heating effect of creating liquid nitrogen to warm homes. In the summer we can use the liquid nitrogen to cool homes. We can also power it through a turbine to create more electricity. Basically the cost of creating liquid nitrogen is the cost of the "extra" electricity being created at off peak times and the cost of equipment for creating/storing liquid nitrogen. It's non-flammable, but still dangerous due to the pressure it can create in vessels and the temperatures of the substance.

There could be other similar ways to save electricity. We could use the spare energy to raise weights up to a height and use gravity to power a turbine. We can store potential energy into springs, or so many countless ways. We just need to keep at it and we will have no problems with energy once we have a way to store it properly instead of just wasting it.