Better Managing Energy Usage

Building on my prior mentioned rising energy costs post, manufacturers are looking beyond optimizing their throughput, quality, and plant availability at how they can optimize the use of energy, since this directly impacts their bottom line.
Changing process conditions causes changes to the plant utility system which impacts: power demand, steam demand, fuel balance, emission targets, and the dynamics of the operation. Effectively managing utility system operations must consider the competing economic and production issues in a timely manner to improve the profitability of the production process.
I spoke with Peter Stanley, an Energy Management consultant in the Performance Monitoring and Optimization business unit of Emerson’s Asset Optimization division. Steve and the team typically see opportunities for a 2-5% reduction in annual fuel bills by applying an Energy Management application to optimize the utility system. This can translate into as much as 25% of utility annual fuel spend.
The first step is to look at the major areas of energy usage. The first area is in the steam balance which is the steam required to provide heat across the site. Units may be importers or exporters of steam, and the amount of steam produced or consumed changes with throughput and operating mode.
The next area is power balance, again by looking at the importers and exporters of electricity. Many plants have on site generation in addition to what they purchase from the local utility, and can export excess power back to the utility grid.
Fuel balance looks at the mix of fuel gas and waste or by products which have little or no value. The objective is to consume in the lowest cost manner that raises the maximum energy for the process units.
Environmental constraints look at NOx and SOx levels and avoiding the maximum limits based upon the regulatory statutes and availability of emissions trading practices.
In addition to changing process conditions based upon what is being produced, the prices of fuel and power changes. Contractual arrangements for the import or export of electricity, fuel, or steam also impact the optimization.
A final area of consideration is the performance of the existing equipment including the boilers, gas & steam turbines, recovery steam generators, etc.
Building a solution with Emerson energy management experts and the AMS Optimizer, it is possible to continually deter the set of operating setpoints that will allow the utility operations to continually run at its economic optimum based upon all these factors and constraints.
Peter describes the approach where Emerson partners with its customers to deliver a guaranteed level of benefits typically within six months for a completed system. Payment for services and software is not due until the end of the project when the guaranteed level of benefits has been achieved.
Peter stressed that all projects have paybacks within 12 months and Internal Rate of Returns greater than 200%. Support of the optimizer solution is provided with a long term support contract.
It sounds like in an era of high energy costs and a solution with performance guarantees, that this is definitely an area to consider if your manufacturing process consumes lots of energy.

Posted Wednesday, April 26th, 2006 under Energy.

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