Windmills and Solar energy ?

Question

The issue is how to store this power after it's made. There is no way Edison is going to let wide spread use of net metering. Batteries are not up to pare. I think hydrogen is a great way. With a fuel cell only the power you need is used. Hydrogen can be used as a replacement for propane and natural gas, its just as safe. Make energy for your house, electricity & hvac.

Fuel for your cars and SUV's.

No more transporting coal across the country or oil across the planet. It's made and used locally.

Answer 1

with the huge demand of electricity in our world today storing it is not the main issue huge solar farms in California and wind farms popping up everywhere as fast as we can produce it it will be used therefore having less dependency on fossil fuels during peak usage times

Answer 2

EDIT: The reverse process of creating and using hydrogen (from a source of electricity) is highly inefficient with 35%.

I therefore base my solutions on the electric grid which the most efficient way to balance demand and supply for power.

PS: Hybrid cars could partly be recharged at night if connected to the grid with the excess power generated.

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There are three solutions:

- storing the excess of energy

- producing on demand the power to balance supply and demand

- adapting the demand according to the supply

* Plus of course all combinations of these 3 measures:

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STORAGE OF ENERGY:

This can be done by:

# Reservoir hydro power plants to which water is pumped from downhill uphill to refill the reservoir when there is an excessive supply of power. This is for example done by Switzerland where water from a lower lake can be pumped into a high altitude lake. This storage has an efficiency over 80%. This is commonly down with the excess nuclear power France has at night for example or with the excess wind power.

# Pressured air: this is done mostly in natural salt layers. The efficiency can be up to 60% (but a large share of the energy would be lost in heat during the compression and little of it recovered in the expansion turbine. Since compressing the air leads to its increase of temperature, the pressured hot air is often used to be mixed with natural gas and run a gas turbine.

#  Batteries: The efficiency of Li batteries is over 95% but there is no viability on a large scale for such a system.

# Fuel cells: only 35% efficiency and an excessive price to store hydrogen. Moreover, the catalyst used can be very expensive

# High RPM spinning devices: It has been proposed to store mechanical power to later on produce electricity in fast rotating steel cylinders in the form of kinetic energy. Rotations speed would be by far over 1,00,000 RPM, under vacuum to reduce friction and through magnetic bearing. Prototypes for 5MW output for half of a day are being tested

# Magnetic field in toroidal supraconductors: this solution is far from being commercially available.

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PRODUCING ON DEMAND:

# Gas turbines can be started and adjusted to the desired capcity in just 15 minutes

# Hydro power plants: if based on a reservoir can adjust their output

# Power plant control: the output of presently running power plants can be adjusted with nevertheless losses, especially if done by throttling

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ADAPTING THE DEMAND TO THE SUPPLY:

Massive users of electricity such as grinding processes, electrolysis (e.g. aluminium production) or electro steel mills have the possibility to adapt partly their load to the supply and demand.

Electric water heater have even a larger potential to adapt their demand since the resistivity is easy to control and the function (heat water) can often be operated at any time of the day.

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Other storages of energy:

# Phase change materials: e.g. molten salts can store energy at temperatures over 700°C which are then sufficient for steam turbine cycles.