Thursday, 21 August 2008

Fuel Cell design with breathable - conductive membrane without Platinum catalyst

Cell casting under vacuum with glass sheets producing less than 0.5 micron thick graphite coating onto modified PTFE substrate is comparable to that of fuel cells using a Platinum catalyst.

Tests have shown that by using the membrane at elevated ambient temperatures of 170oC and a voltage range of 120-200 VDC pulsed (quenched), acts as both electrode and catalyst and is comparable to similar tests undertaken with Platinum and other noble metals at lower temperatures.

This new doped material allows O2 exchanges from water vapour (steam) but is totally impervious to water droplets in the process.

The new fuel cell design allowed ionic exchanges through the membrane for 24 hours continuous with water as the fuel source.

Further tests are required to increase and collect oxygen from water using pure nickel electrodes in a simultaneous process wherein a potassium hydroxide (KOH) electrolyte has shown to produce pure oxygen at the cathode thereby providing a higher volume of hydrogen in the presence of the new membrane at the anode. The reverse is also true as with the graphite coated membrane/electrode above, which also produces clean oxygen at the anode without reversing polarity.

Wednesday, 20 August 2008

Hydrogen storage is not the answer to a hydrogen economy

Storing gaseous or liquid hydrogen in containers is difficult, dangerous and futile.

The hydrogen economy is far from realisation due to some scientists and engineers insisting upon overcoming these technical problems.
Unfortunately hydrogen storage has no place in the hydrogen economy we are seeking but for a few on-site facilities where it is both produced and used directly or, converted to electricity at source and distributed through the national grid.
The answer lies not with storage but on-site and insitu production.

Read more >

Tuesday, 19 August 2008

What is a fuel cell?

A fuel cell is an electrochemical energy conversion device that takes stored chemical energy and converts it into electrical energy directly.

In the presence of an electrolyte (which also acts as the reactant separator) and electrodes (which act as the catalyst), a fuel cell produces electricity from fuels such as hydrogen and oxygen. The current is collected externally at the bipolar plates.

A battery has all its chemicals stored inside it, and it too converts those chemicals into electricity but unlike a fuel cell, batteries eventually "go dead" through depletion and have to be either discarded or recharged.

With a fuel cell however, chemicals constantly flow into the cell so it never goes dead. A continuous replenishment of fuel into the cell, provides near continuous electrical production. Most fuel cells in use today use hydrogen and oxygen as the chemicals and as such, the conversion of fuel into electricity via the electrochemical process is considered clean, quiet and highly efficient typically two to three times more efficient than combustion.

In addition to low, zero or near zero emissions, other benefits include high efficiency and reliability, multi-fuel capability, scalability and ease of maintenance. Fuel cells operate quietly, so they reduce noise pollution as well as air pollution and the waste heat from a fuel cell can be used to provide hot water or space heating for a home or office.

Many combinations of fuel and oxidant are possible. A hydrogen cell uses hydrogen as fuel and oxygen as oxidant. Other fuels include hydrocarbons and alcohols. Other oxidants include air, chlorine and chlorine dioxide etc.

Sunday, 10 August 2008

The Hydrogen economy - By Default

How many times does something have to be rediscovered?

This is a real life experience for many individuals, industry and other organisations within their respected academic and experimental capacities to pursue technology and a costly one.

It is far less apparent in industry with huge teams of researchers and managers with seemingly large resources than it is for the individual or small group, but the problem of rediscovery exists at all levels.

Technology perpetually feeds itself in a particular area but cannot encourage growth or provide potential to other areas which may be applicable without publication or demonstration (sharing). This is true in both specialised areas of scientific research and basic research at all levels.

Hydrogen and our understanding of it as a propulsion technology - as in the case of rocket fuels, and our fear of it as an explosion (as in the Hindenburg explosion) caused the scientific community and others to abandon it as a viable fuel primarily for safety reasons but partly because of other emerging "safe" technologies at the time with the emerging alternatives as hydrocarbons, ethanol/oxygen and because it was less technologically taxing.

Abandonment of hydrogen has been historically a recurring problem. Many theorists and researchers had considered using hydrogen as a fuel but had failed in the pioneering days to produce it in significant quantities, contain it without acceptable evaporative losses/leeching and later to safely exploit its use as a fuel significantly, especially in an ideal mix ratio: H2/O2 (2:1). The widespread fear of hydrogen in modern society, probably originates with the well known disaster of the Hindenburg dirigible and reinforced by the H-bomb. Proponents of hydrogen however thankfully overcame that prejudice (hydrogen-fuelled rockets are now a reality). Other technologies are undoubtedly ignored today simply because of the same bias against certain materials or processes. Supposedly in part through ignorance and preconceptions through histories prior abandonment, but also with a certain unwillingness to overcome those technological barriers through fear of failure. This fear of history repeating itself might account for the lack of sharing of information and consideration of postulation by others. Engineers and scientists, just like the rest of us remain conditioned; we need to be reminded occasionally to take a fresh look and approach old attitudes and familiar procedures without fear of ridicule or scepticism.

The author hereby empathises with the often conflicting roles of the individual researcher or experimenter, who originates ideas and concepts and that of the group or organisation which manages/oversees today's complex hydrogen technology. Many worthwhile ideas have undoubtedly been lost, at least temporarily, because individuals were unable to convince managers and academia without specific articulation, language or expression. Consensus is achieved within groups by appointed engineers and scientists often with one or more individuals pulling rank or seniority. When agreement seems impossible in such a situation, an individual is occasionally bold and arguably wise enough, to forego his preferred solution, so that a project may continue unhindered. In this regard, timing is critical. If the individual does not argue his ideas effectively or hard enough, he is seen as indecisive and unconvincing; but if he forcefully and frustratingly makes his case he is obstinate.

The decision to use liquid hydrogen/Oxygen in the upper stages of the Saturn launch vehicles cites many accounts of individual/group interactions from which any individual and decision maker alike can profit.

It is true that a hydrogen economy is far from becoming a reality - short term, and I concur with those who state that we cannot employ the same methods used to propel rockets in our cars. But until we start collaborative efforts at all levels, and by ignoring our fears and readdressing at least some old technologies even to affirm or substantiate claims will we ever see it happen.

Authors note:
I have purposely made reference here to "old technologies" as a precursor to the consideration of using particular "forgotten technologies" which through experimentation with the old and the newly emerging technologies, will publish in due course. However to substantiate my findings it will be necessary to provide constructive argument to current and emerging technologies with emphasis on certain known limitations without being outright dismissive. The old technologies with which I propose are to be merged with the new as these will be proven and substantiated as; viable and complimentary.

I welcome your comments.