Power Struggle: Solar vs Fuel Cell

It is a good sign that new renewable technologies like fuel cells as on par alternates to solar cells are emerging out. We need all possible avenues of course.

The limitation as it appears to me is the low load capacity like home based, lighting or low load utilization only.

The main concern is the lakhs of MW grid demand and the high load requirements that no renewable energy tech is capable of meeting including wave, tidal and wind.

Thermal remains unchallenged yet.

Bloom Box is very short on details (of the fuel cell).

The main component of the stack made from sand (which is everywhere) - really????

Sounds like glass to me which would melt at SOFC temperatures.

Less hype and more details so we can really see if it is the answer to a sensible question.

Glass is like ceramic but unlike glass ceramic will withstand much heat...

In terms of micro (user site based) generation of electricity I believe the technologies are very complimentary. PV is all you say it is but lacks a simple and 'clean' provision for storage. Storage is key to operating a microgrid (site capable of being 'islanded' or off-grid for long periods of time).

As I understand it, the Bloom FC does have the capability of being 'reversed' (taking in electricity) to produce (and store) energy in the form of hydrogen which can later be used as a 'clean' fuel in the normal operation of the cell. Its downside is, without hydrogen, the other fuels it runs on aren't as 'clean" (although they beat the heck out of burning coal or oil which is how most of our electricity is produced today). The combination of PV and the fuel cell is therefore likely the best approach. One could use PV when the sun is available to run things AND to produce stored hydrogen fuel (especially when the loads are minimal - like on weekends and other holidays) and then reverse the fuel cell to produce electricity when PV generation is unavailable or insufficient to keep up. For longer periods of local under production or peak load, one could either use the fuel cell on an alternate fuel (i.e. natural gas or a bio-renewable) or chose to buy power from the utility macrogrid.

I'm probably oversimplifying the material balance factors here, but there's not enough info published on the Bloom cell to make a calculation of this sort. I do believe the Bloom cells are scalable (I think in 25KW increments) so it's not an all or nothing deal if the site use of electricity is higher than 50KW. You could use a portion of the cells for storage production and a portion for PV supplement.

I'm a huge PV fan myself, but I know of many buildings that just aren't that suitable for an all PV approach, even when power storage isn't a factor. As you go up in stories, the ratio of roof and suitable facade space is inadequate to locate enough PV cells to produce all the needed electricity (not to mention the problem of 'shadowing' from adjacent buildings and structures during different times of the year. In this case, an even higher proportion of the power needs to come from the fuel cell.

Bottom line is we really can't afford to overlook the probability that combinations of microgeneration technologies are most likely going to satisfy power needs for the widest variety of site and use variables.

And speaking about combinations, we should be looking at switching as many loads as possible over to DC (the native form of electricity that both PV and FC produce) so we can simplify the routing and coupling of power generation sources, reduce the number of lossy power inversions/conversions, increase the quality of the power itself and increase the overall simplicity and reliability of the electrical equipment and devices using the power. We're in the digital asyncronous age (code for DC) so why is it we keep trying to exclusively use syncronous analog (code for AC) power? Ever feel the heat coming off your laptop or cell phone power converter? Heat=waste energy. Multiply by 2x plus if you're in an air conditioned building. But that's a whole other, albeit related, subject.

Hydrogen is the perfect storage media for solar. Electrolysis to capture unused Hydrogen from water during the day. Use Hydrogen in fuel cell at night. The best is to use more than one source for energy.