Energy | Global energy strategy begins with control | Control Global

CAN I COME IN, NAGYPAPA?" ASKED IVAN, my 9-year-old grandson, knocking on the office door. (Nagypapa is the Hungarian equivalent of Grandfather.) "Uh-huh," I answered. "What are you writing about, Nagypapa?"

"About fixing our old refineries."

"Aren't they those ugly chimneys that smell bad? Why dont you write about something nice?" he asked.

Well, it was this conversation that started me thinking about the greater responsibilities of my profession. So, for the time being I stopped writing about the danger posed by our "digital Babel" when modernizing our ancient refineries and decided to write on a different topic:

We all know that oil will run out by the end of this century. We also know that a gradual transition to a clean and inexhaustible energy source will take decades. Yet we have not even started on this road of transition. We have not started, because there is no agreement on where we should be heading and what we need to do to get there.

THE ENERGY BELT
The total energy consumption of mankind is around 1017 BTU/yr. About a half million BTUs of solar energy are received every year by each square foot of area at the Equator. Therefore, thoretically, a couple of hundred yards-wide equatorial belt receives the same amount of solar energy as our global energy consumption.

To overcome this mental roadblock, we in the field of technology, and particularly in the community of control and automation engineers, have the responsibility to initiate a debate, which eventually will lead to an agreement. It is for that reason that I have prepared an "Energy Road Map" that could lead us to a clean and inexhaustible energy future.

Energy Road Map for the 21 ^st century
Start by building gigantic, floating islands covered with solar-collectors and positioning them around the Equator. It is not likely to cost more per installation than a deep-sea oil platform. Use the solar energy to make hydrogen from sea water and condense it into a liquid-slurry. Air Products is one of the companies already working with hydrogen slurry, and more companies will surely join in.

Using the resources of existing gas handling companies we could design cryogenic tankers and trucks to distribute the hydrogen-slurry to fuel/gas stations around the globe. It wont be easy. Although fuel cells performed reliably in space exploration, the design of cryogenic tankers and trucks is not an easy task and is questioned by the Europeans, who prefer the high pressure gas storage approach (currently up to 10,000 psig). The resolution of these issues will be neither easy technically, nor politically.

Well need to install standardized hydrogen storage tanks with fuel cell generator units at all fuel stations. Much further development is required, because todays fuel cells still cost about $100/W and the size of a 40 kW generator is still five times that of its diesel equivalent.

We will still need to convert the chemical energy of hydrogen into electricity and store it in battery blocks to power electric cars for 300 miles. The battery blocks should be external, weatherproof and replaceable quicker than the time it takes to fill up with gasoline today.

Well have to convert todays gas stations to dual-purpose ones, so that during the coming transition period, when an electric car or truck arrives, its depleted battery block can be quickly replaced by a fresh one. Well also have to design methods for handling the recycling of batteries as they become old and inefficient. We should set up a Global Academy of Science to direct the safe and gradual transition to the use of this inexhaustible and clean energy source around the globe.

"Let our profession take the lead by having ISA set up a task force to develop a multivariable controller for the hydrogen filling station of the future..."

We can design scaled up, larger stations for industrial and power plant use and smaller ones for providing heat, cooling and electricity to private homes. To eliminate conflicts of interest and to take advantage of experience, we must include the same firms that operate the refineries, distribution network and fuel stations today in the transition from an oil based to an hydrogen based economy.Let our profession take the lead by having ISA, or another engineering society, set up a task force to develop a multivariable controller for automating and globally standardizing the controls for the hydrogen filling station of the future. The challenge in controlling a 400-cell stack of fuel cells is similar to the task of controlling a 400-cylinder engine. The specific control challenges include the development of:

Neural and model predictive fuel cell control algorithms (which also provides preventitive and predictive maintenance),
Low-cost throttling control values for 1,200° C low-flow and high pressure service,
Inexpensive flow and O2 sensors, so stack and individual cell performance can be monitored cost-effectively,
Thermally insulting optical sensor leads for 1,200° C service to help eliminate the heat losses.

I realize these goals are quite ambitious, but if we look back at the technical achievements of the 20^th century, they might seem more realistic. In the 4^th edition of my handbook, high-temperature fiber optic sensors are already discussed. Similarly APC controls are covered, which can integrate the hydrogen slurry and fuel cell controls with the battery replacement robot controls into a single unit operation controller.

Wouldnt it be great if ISA decided to set up a task force to do this? Wouldnt it be nice to see the instrumentation and process control profession recognized as one of the leaders of the effort to solve the energy problem? And wouldnt it be great, if our little Ivans could say to their grandfathers, "Nagypapa, this was nice!"

BÃ©la LiptÃ¡k, process control consultant and columnist, is also editor of the Instrument Engineers' Handbook and is seeking new co-authors for the forthcoming new edition of that multi-volume work. He can be reached at [email protected]