Pentti J. Aalto 

PJA Energy Systems Design 

720 Bachelder Road 

Pembroke NH 03275 

603-485-2559 

pjaesd(a)comcast.net 

6/30/04 

Department of Environmental Protection 

Bureau of Waste Prevention 

One Winter Street 8t h floor 

Boston MA 02108 

Attn: Robert Donaldson 

RE: Response to New Rules for Distributed Generation 

Dear Mr. Donaldson: 

Thank you for the opportunity to comment on the proposed rules for distributed generation. The purpose of these 

comments is to amplify and expand my verbal comments in Boston on June 22, 2004. The comments are based on 

over 30 years of experience in the areas of energy conservation, district energy, cogeneration and the institutional 

and regulatory issues related to them. I was a founding member of the New England Solar Energy Association (now 

the New England Sustainable Energy Association). I designed a project that became the Governors Commission on 

Cogeneration. I am a past member of the International District Energy Association where I was active in the 

research committee. I have been actively involved with cogeneration system emissions and their control during this 

period. 

I will discuss issues relating to the proposed rules for distributed generators (DG), their purpose, risk of less 

stringent rules. Further, in subsequent comment I will propose in more detail alternate market-based, regulatory 

system that I believe will provide better results over time at relatively low administrative cost. 

These comments represent my views only. 

Purpose 

Distributed generation has the potential to make dramatic improvements in both the environmental and economic 

impacts of energy production. The problem is that the commercially viable DG technologies that are available today 

have not had the focus that central station plants have had. New central plants are often cleaner than today's fuel 

burning DG technologies. If we are to gain the advantages of DG we must establish rules that allow the opportunity 

for existing technologies to improve while protecting the public health. The resources necessary for research and 

development of these improvements will be available if a market exists for them. Emission rules can help or hinder 

the development of these improvements. Rules that are too loose provide little incentive; rules that are too strict will 

stop development when alternatives are available. In this case, conventional central station power is usually 

available. 

Risk 

Substantial rapid development of DG using existing technology would increase emissions. Two areas where this 

might occur are the use of existing emergency generators for non-emergency economic uses, and the development of 

new systems to replace purchased power. 
Emergency generators are usually designed to operate disconnected from the utility grid. This allows safe operation 

of the generator when utility power is down. The circuits to be served by the generator must first be disconnected 

from the utility's wires before the generator can be used. This results in a disruption in service that can be a problem 

for sensitive loads. The generator must also be substantially larger than the average load to allow starting surges to 

be accommodated. This results in operation at inefficient reduced load. 

The high cost of operation in this mode severely limits the economic value of operation as a way to save money. 

Efficient loading of the generator can be accomplished by interconnecting with the utility. This requires expensive 

protective equipment and studies that again limit the application to systems where particular situations exist, such as 

transmission or distribution congestion. Operation in either of these non-emergency modes is economic only in 

particularly high cost areas and only for short times. It is unlikely that overall emissions would seriously deteriorate 

and might actually improve if the operation displaced older central plants or spinning reserves. While these systems 

might operate during bad air times, it is unlikely that they would cause significant deterioration because relatively 

small amounts of power would reduce prices to non-economic levels. Air quality risk is small. 

Larger effects on total emission tonnage could occur if large quantities of low cost fuel or high efficiency were 

available through cogeneration. Of these, cogeneration (or combined heat and power CHP) is the most likely. 

In cogeneratiion systems waste heat from power production is used to displace fuel that would otherwise be used to 

produce the heat. In many European countries, this takes the form of large central power plants connected to district 

heating systems. The waste heat from the power plants is distributed to heating customers for industrial, domestic 

hot water, space heat and other uses. This highly-efficient system requires a thermal distribution system, usually hot 

water or steam. 

In this country, we do not have extensive district heating systems and must rely on other methods to gain the 

advantages of cogeneration. We must site smaller generators closer to heat loads and add heat recovery systems to 

capture the normally wasted heat. While evolving systems such as fuel cells and Stirling engines can be applied 

with heat recovery, they are not generally cost effective today. The highest potential available today is from high 

efficiency reciprocating engines and gas turbines. 

The market for cogeneration systems has been slow to develop for a number of reasons, particularly the high cost. 

This has not changed with the changes in the electricity markets. Even if there were no additional regulation the 

development of these systems would probably continue to be slow. While the risk is small there is a potential for 

growth that requires regulation of emissions. 

We should recognize that those systems that operate little have little air quality effect. Regulations should provide 

added incentives for improvement for equipment that runs more and should continue to promote improvement in 

existing systems. 

The proposed rules fail to provide proper incentives to accomplish these tasks. 

I will provide further detailed discussion of an alternate market based method, which I believe will provide the 

proper incentives. 
Page 1 of 1 

Donaldson, Robert (DEP) 

From: Thomas Hyland [thomashyland@clarityconnect.com] 

Sent: Wednesday, June 30, 2004 3:51 PM 

To: Donaldson, Robert (DEP) 

Subject: DG regulations: comments of Pentti J. Aalto 

6/30/04 

Dear Mr. Donaldson: 

This is a response to the proposed distributed generation rules. I will submit further discussion on an alternate system of regulation that may 

provide better results. 

Thank you. 

Pentti J. Aalto 

7/1/2004