Base Load Solar Power

A frequent criticism of solar power is that the sun only shines brightly for part of the day, and that many of the times when there is significant electrical load (EG when people get home from work in winter) the sun light will be weak. One interesting solution to this problem is to store the solar power by splitting ammonia into nitrogen and hydrogen gases, storing them separately, and then reacting them to produce super-heated steam for power generation at any time that power is needed. The technology is based on three decades of research at ANU and the Federal government has allocated $7,400,000 for building a power station near Whyalla in South Australia.

The down-side to this is that it needs water for the steam part of the electricity generation process which is a minor problem as we are having water shortages in most parts of Australia. But the up-side is that the process of combining nitrogen and hydrogen to produce heat should be something that can be turned on rapidly. So it seems that there is potential for having a wind power plant designed to satisfy all the power requirements on windy days and store hydrogen and nitrogen for times when there the combination of sunlight and wind is not adequate to satisfy the power requirements.

Previous plans for the maximum possible use of renewable energy in producing electricity have included gas fired power plants for times when wind and solar power can’t meet the demand. It seems that with technology such as this one it will be practical to have all electricity produced from renewable sources of energy.

8 comments to Base Load Solar Power

  • Bob

    The water requirement doesn’t seem like a big deal:

    1) It doesn’t have to be FRESH water, build it on the coast (presumably that’s where most of the power usage is anyway) and use seawater for the condenser. Inside the steam loop itself you can recycle the water so barring leaks you fill it once and you’re basically done.

    2) A backup gas-fired plant of the same capacity is going to have essentially the same water requirements. The main solar plant itself could be based around a steam turbine, for that matter.

  • etbe

    Bob: You are correct that gas fired plants will have the same water requirements in this regard. However wind power has a significant advantage in that the only water requirements are for occasionally washing the turbine blades.

    As for recycling water, you won’t get close to 100% water efficiency without sacrificing power generation efficiency in the process. The choice of wasting water when we have water shortages due to climate change and wasting fuel use which causes climate change is not a good one.

  • ARP

    How can I get more information on the system? I guess that part of the process’ heat can be used to evaporate seawater and use the resulting distilled water to run the steam power generation, right?

    Is there a patent in this process?


  • etbe

    ARP: Desalination is expensive no matter how you do it, and I believe that distillation is not the cheapest method, although combining distillation and steam production (go-generation) does reduce the cost.

  • Rob

    What’s the efficiency of this process?
    As a storage mechanism, how does it compare, for example, to simply pumping water up a hill into storage during off-peak periods and releasing it through turbines during peak periods/overnight?

    This system is already used in the current power grid.

  • Base load solar power statioon is feasible at (on current costs) at 65% of the diesel energy cost.
    fresh water can be produced at less than a fraction of the standalone Desal plant if integrated with the power plant.
    The overall efficiency (estimate) is betther than 60%.
    The water consumption within the power plant (solar /steam) is only makeup water as the cycle is close loop.
    It is the energy in the condensate that is recovered in distillation.
    the energy required for distillaton is minimal approx 4kWe/cu.m water.
    M. Ali

  • S

    The main drawback with this as far as i can see, is that we are still at mercy to the weather. If its going to be cloudy for a week or more, and as a result these plants will not be operating at capacity, can you really call it a base load solution?

    People never talk about intermediate alternatives like nuclear power, which gives off almost no greenhouse emmissions, and we have uranium in abundance, but we just need to build a place to store the nuclear waste. Ironically the people who make the most noise in the nuclear debate are those who cannot even explain in detail how nuclear fission works, just that “nuclear is bad, mmkay”

  • etbe

    S: Part of the solution to the energy problems is to have large distributed grids. There are currently plans to have solar power from Africa supply Europe. If you have solar power stations spanning a continent then any event which disrupts sunlight over an entire continent for a week is probably going to be a bigger problem for you than the lack of electricity. Apart from areas close to the poles, the only way you can have a lack of sunlight over a large area for a week would be from a “dinosaur killer” meteorite or nuclear war.

    Nuclear power is not intermediate because it takes longer to build the nuclear power stations than it takes to build renewable energy sources.

    The people who advocate nuclear power generally don’t understand the safety issues related to nuclear power plants and have not even considered the terrorism issue.