Almost a year ago, a company called 'Bloom Energy' hit the headlines. The founder of the company K. R. Sridhar gave presentations and interviews on what it is, how it works and how it can solve many inefficiencies in current electricity production and distribution. What was more surprising was Bloom Energy has been producing fuel cells and has installed them in corporate offices of several big corporations like Google, Bank of America, Walmart, etc. Almost sounded like some undercover operation.
A brief explanation on what it actually is:
Bloom Energy uses hydrocarbon based fuel cells, which it calls 'Bloom Box' or 'Bloom Energy Server' that takes in hydrocarbon (eg. Natural gas) and passes it through plates coated with a special catalyst. One of the plates is the cathode and another the anode. The catalyst helps break down the hydrocarbon into CO2, H2O and electricity. We are not going to look into the details of the technology itself, but we are going to focus more on how a concept like this can revolutionize production and distribution of electricity.
Could Bloom Energy really deliver? It seems like a very good idea. By looking at the concept, it seems to solve two major inefficiencies in the current system:
1. Production inefficiencies
2. Distribution inefficiencies
1. Production inefficiencies:
Currently most electricity is produced by converting mechanical energy into electrical energy by driving an electric generator. The mechanical energy to drive the generator is derived from steam which in turn derives its energy from coal, sun or radioactive elements. Some are more direct, like wind energy farms for example, energy from the wind is converted to mechanical energy which is then converted to electricity, and natural gas and diesel power plants also involve fewer steps. The most direct do far has been using solar cells but they are very expensive and the technology is still young. But as we have seen in most cases multiple energy conversions are involved before we get the final product - electricity. The more the number of conversions, the higher the energy losses. In each step of the conversion process energy is lost A quick look at some of the popular processes of electricity generation:
Coal, Solar (Thermal energy based), Nuclear power plants:
Heat from Coal, Sun, Nuclear reaction -->Convert water to steam-->High temperature high pressure steam runs the turbine-->Turbine runs the generator-->Generator produces electricity.
Natural gas, diesel power plants:
Natural gas burns to run the turbine/Diesel burns in IC engine -->Runs the generator-->Generator produces electricity
Wind power plants:
Wind turns the turbine-->Turbine runs the generator-->Generator produces electricity
On the other hand, Bloombox or the Bloom Energy server as it is called directly converts chemical energy in fossil fuels into electricity, producing CO2 and H2O in the process. In short it would look like:
Natural Gas-->Electricity.
This makes the Bloom Energy server very efficient.
Is this the only fuel cell capable of converting chemical energy directly to electricity? No, there are several, especially ones based on Hydrogen. But that again poses serious problems, like production of Hydrogen, which again costs a lot of energy, and distribution and storage of Hydrogen, which is a highly explosive gas.
Most cities already have natural gas pipelines and several new gas wells have come up recently with urban gas drilling, and natural gas is so easy to extract and distribute. These factors give natural gas based fuel cells a definite advantage over Hydrogen fuel cells
Hence, considering production efficiencies of several power plants and technologies out there, the bloom box certainly seems to be a clear winner.
2. Distribution inefficiencies:
Most power plants are situated very far from major consumers. No one wants a coal or nuclear power plant in the suburb or downtown. Even clean energies like wind and solar need vast areas of land, which means they need to be located far away from civilization. The current model of electricity distribution is very inefficient. Eletricity is produced in power plants situated far from major cities and industries and is then supplied to the grids. The grids on the other hand are connected to several grids and switching stations that control the distribution of power based on load requirements. Then there are sub-stations that are connected to the grid that 'step-down' the high voltages for local distribution, which is then even stepped-down for household distribution using transformers.
In brief, the model is more of a 'centralized' model than 'localized'. Such a centralized model requires vast distribution networks that may run thousands of miles, multiple switching stations, multiple transformers performing multiple voltage conversions. Before the electricity reaches the consumer, it is switched from one grid to another, from one sub-station to another, the voltages 'stepped-up' and 'stepped-down' multiple times using transformers before finally reaching the consumer.
Similar to what we saw in the 'Production inefficiencies' section, the more the number of voltage conversions, the more the losses. The farther the electricity is transported the more the losses. Transmission and distribution losses are a major inefficiency in the current model of electricity production and distribution.
Moreover, such is model is very susceptible to natural disasters and is vulnerable to terrorist or military attacks.
Bloom Energy model is very localized. Energy is produced right where it is needed. No transmission or distribution, no need for voltage conversions (Unless a higher or lower voltage is desired). It could be right in your backyard, or in a neighborhood supplying for the whole community. Every office building may have one in its block. There no one sub-station to fail and plunge a whole suburb into darkness. There can even be mini grids within a city or a town with many bloom boxes backing each other up in case one fails or one is shut down for maintenance. Such mini grids may be much more efficient than transporting electricity half the way across the country.
When considering distribution, the Bloom Energy is again a clear winner.
Bloom Energy certainly has good prospects in the future. The model is very attractive and efficient. Even though it still uses fossil fuels, it makes the best use out of fossil fuels, and hence can still be considered 'green'. It is still far less polluting than other fossil fuel based plants. There may be exciting new turns in the near future in the energy field.
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