PASHAs for management of electric energy consumption

The management of the distribution of electric energy has been undergoing a drastic change since the deregulation of electric utility companies, which has uncoupled the production and distribution of electric energy. The deregulation is changing the business of electric utilities from one of just selling energy to one which includes various elements of service, with the service content likely to continue increasing in the coming years. It will affect the distribution of energy to all customers, from housholds to large commercial sites.

Service to households

Electric energy is currently sold to consumers using very simple, and parhaps outdated, methods. Consumers are charged a fixed rate per kilowatt-hour, or at best a dual rate involving reduced charges for appliances operating during the off-peak hours.

Emerging competition among energy companies, stimulated by growing deregulation of energy monopolies, may force these companies to re-think their pricing strategies. One possibility may be to allow virtually every appliance to negotiate the best time of operation, and a correspondingly reduced price of energy. This can be accomplished by mobilizing a PASHA which will activate some or all the appliances of a household in a way that optimizes timing and reduces cost to the user. The PASHA would be programmed to follow the commands of a user, and either carry out the task of an appliance immediately or negotiate with the electric company an optimum time and price of operation. The PASHA would reside in a computer, either the user’s or the utility company’s. The PASHA would negotiate energy use for a number of appliances and activate them through remote switches. Full imlementation of PASHA capabilities, including advanced user interfaces, would facilitate making desired changes, regardless of the location of the host computer.

Service to large commercial sites

Large electric utility customers have considerably more complex needs than households, and they are served differently. The needs involve considerations of containing the cost of energy, guaranteeing satisfacory performance of equipment that uses electric energy, and satisfying environmental quality requirements.

The cost of electricity to a large commercial customer is often determined not only by total consumption but also by the level of peak demand. Thus, it is advantageous to a customer to suppress the peak demand if at all possible, in addition to containing overall consumption.

Performance monitoring involves, first of all, guaranteeing that a piece of equipment operates always within an allowable range; for example, a freezer stays within an allowable range of temperature. In addition, monitoring of appropriate sensors aims at detecting incipient failure of equipment and calling for preventive maintenance.

Finally, environmental quality control involves monitoring and controlling air quality, such as ambient CO2 level, in order to initiate possible corrective action such as increased ventillation.

It is easy to see that the above requirements are intertwined, since minimizing energy consumption and/or suppressing peak consumption is influenced by distributing energy to the entire range of equipment in order to satisfy performance and environmental control requirements. This leads to a complex task requiring the following the following capabilities of a management system:

Prediction: The system must be capable of anticipating fairly accurately the demand for energy of the entire site and its various units of equipment.

Scheduling: The system must schedule the consumption of energy in order to achieve consuption objectives, such as suppressing peak demand and minimizing overall consumption.

Monitoring: The system must monitor the performance of all equipment to guarantee satisfactory performance and environmental quality, and detect incipient failures.

Real-time adjustments: The system must be able to make real-time adjutments of the operation of equipment in order to achieve desired performance levels, in response to unanticipated fluctuations in demand, weather, and any other conditions influencing equipment performance.

As the level of complexity of a system providing the above services increases, a customer is faced with yet another problem, namely, finding janitors capable of running the system. Let us see how a PASHA can meet all these challenges.

a) Basic PASHA databases

A PASHA residing in a computer at the site will be linked to sensors and to every piece of equipment at the site, and also to the internet. The PASHA data base will contain data of past activities at the site, historical records of past energy consumption, and other relevant information such as past and expected weather conditions, projections on future events which may influence the activities at the site, etc. The database will also contain profiles of individual equipment units consisting of normal readings and indications of readings warning of possible incipient failures.

b) Input collection and preparation

The PASHA will receive sensor data from the site containing information concerning activities at the site, operational characteristics of the various pieces of equipment, and environmental quality measurements. It will also receive, over the internet or through direct communication with relevant information providers, such information as current and projected weather conditions, and any events likely to influence the performance of the equpment at the site such as those that might produce unusually large crowds.

On the basis of the above data, the PASHA will define, in real-time, a projected allowable range of operational characteristics of all pieces of equipment, such as lighting requirements, ventillation requirements, and cooling requirements, and the associated levels of energy consumption.