A secure, renewable grid
In a May 29 speech, President Obama announced the creation of a White House position on cybersecurity to protect U.S. infrastructure, including a vulnerable electric power grid, from cyberattacks.
The good news is that we can make decisions now to build a renewable grid that is inherently secure and highly resistant not only to cyberattack but to conventional sabotage.
This is a continental-scale renewable grid that can provide us with economical power, end our dependency on foreign oil and polluting coal, and deal decisively with the global climate change.
A renewable grid is not just a fanciful dream. My associate, Dr. Gregor Czisch, has modeled the operation of a continental European supergrid. We are currently developing plans with other scientists for modeling a North American supergrid.
The existing grid system is both highly polluting and extremely vulnerable to both cyberattack and sabotage. A small number of large power plants are responsible for keeping the grid in balance. Control systems send and receive signals using a mixture of private and now often public networks, including the Internet, that can and have been easily penetrated and salted with disruptive malware.
Transmission systems are often designed in a radial or spoke fashion using a small number of large transmission lines where failure of more than a single major line can result in huge blackouts.
A secure 21st century renewable grid system, in contrast, would ultimately be based on many thousands of large renewable generators and storage devices feeding a high-voltage direct current transmission web able to move power long distances over multiple paths to where it is needed, combined with many millions of decentralized distributed generators and storage devices.
These millions would include basement cogeneration systems, voltaic, heat pumps, flywheel storage and electric car batteries.
The system would be substantially self-equilibrating. Devices would be designed to detect and to maintain electric frequency and voltage within acceptable operating ranges. For example, as the load on the system increases and voltage or frequency decreases, end-use devices would be programmed to reduce consumption, flywheel or battery storage would put power into the system, home generation would increase output. In effect, these devices without central control signals would act in the same way as current automatic generation control signals now sent on suspect networks.
In addition, the smart grid can be optimized economically by broadcasting price signals — for example, by satellites, to receivers on end-use devices programmed to respond to price rises or falls. And if the satellites were sabotaged or false signals sent, end-use devices would lock out signals that conflicted with their measurements of local voltage and frequency.
My associate, Pentti Aalto, and I have developed a working prototype of a control for end-use devices that responds to utility price signals broadcast by a satellite pager network. Next step on our agenda is to combine this with frequency and voltage control.
There’s a lot of smart programming and control work that needs to be done to make sure that multiple distributed generators are properly coordinated, that sensors provide proper information of grid conditions, that careful plans and protocols for interconnection and getting from current systems to a fully renewable grid are developed.
The central point is that for a fortuitous combination of security, energy, economic and ecological reasons we can choose energy systems and control scenarios that are inherently durable and highly resistant to cyberattack and the designs of those who would do us harm.
Roy Morrison is director of the Office for Sustainability at Southern New Hampshire University.
