Cogeneration (CHP, CCHP)
Cogeneration systems are installed in a variety of facilities to optimize energy use and cost. It does this by “multi-tasking” the fuel that is consumed to meet the electrical, heating, and cooling needs of the building. Optimizing fuel consumption means we optimize the energy cost and the carbon produced.
Cogeneration systems come in a wide range of capacities. Larger systems might be located in a manufacturing facility or university campus. Smaller systems (less than 1000 Kw) typically fit into individual buildings . Our portfolio consists of smaller systems we have retro-fitted into existing buildings – this is our wheelhouse and we are very good at it.
This includes general preliminary assessments of the site, as well as detailed energy use analysis via building/energy management systems or our Tru-Use™ meters. This part of the process is where we determine what type and capacity cogeneration will make the most sense for the facility.
This is also the part where we will tell you if we think a cogeneration system just won’t work with your facility. If a cogeneration system doesn’t make sense, we will help you find other options for your facility to optimize building energy cost as well as carbon footprint.
There are significant grants and incentives offered for cogeneration projects nationwide; these incentives vary by state and can be found using the EPA’s dCHPP. We have assisted with grant application for many years so we are very familiar with the process, and strive to make it as quick and effective as possible.
For the majority of our cogeneration projects implemented over the last 20 years, funding has been provided through NYSERDA. These were initially implemented to show cogeneration as an effective energy cost optimization option and, after the 2003 Northeast Blackout, to showcase cogeneration’s ability to provide effective and reliable stand-by power. These programs succeeded in establishing cogeneration as a “mainstream” energy system, and provided a depth of knowledge regarding the feasibility, design and implementation of cogeneration. They also resulted in the growing catalog of proven packaged cogeneration systems to chose from, in order to best match a facility’s needs.
More recently, New York State has prioritized renewable technologies to reduce fossil fuel use and carbon emissions. Funding for CHP systems is now focused on “hybrid” combinations such as CHP with energy storage and other similar combinations.
Power Purchase Agreements (PPAs) are an effective approach to upgrading or replacing building systems at no cost to the facility. Through a PPA energy is provided to the facility at a reduced cost while project cost is carried by the PPA provider.
DSMEA has been involved in PPAs of various types, providing consulting services to the owner or manager of the facility. Our objective is to provide an impartial evaluation of the agreement, so that both parties will attain the benefits they “sign on” for with each other. While PPAs can seem very attractive to a facility needing significant work (but not wishing to spend the required capital), the details and terms must be carefully evaluated to ensure the agreement is not short-changing one party.
Details of these agreements that we have found to be of primary concern include the equivalent cost offset within the facility by a cogeneration system (specifically, what boiler efficiency is used to calculate offset costs), how to verify the actual electrical offsets (demand and enegry), as well as the electrical offset cost.
Post-installation review of PPA performance, such as our CHP ROI Guardian service, provides both parties with accurate and impartial review.
DSMEA is an Mechanical engineering firm. In addition to cogeneration, much of our work is with other building systems like boiler and chillers, as well as the systems in individual apartments, like fan coils and heat pumps.
Cogeneration systems are basically boilers that produce electricity and our focus on cogeneration does not change our focus on mechanical engineering. Many of our projects also include components such as supplemental boilers for heating and domestic hot water, and chillers to supplement/back-up the cogeneration system.
Control systems are also a key part of the majority of our projects; proper control and monitoring are always going to be a critical component of the design and operation of the system. Integration of sophisticated and complex projects with multiple components and subsystems through the control systems is increasingly the differentiating factor between good projects and exceptional projects. We cover a range of control systems from basic and relatively autonomous component-based control for more basic projects, up to full BMS systems with graphic user interface.
In New York City, since Superstorm Sandy, maintaining basic/essential building systems has become a key objective to enable occupants to remain in their homes even during such outages. While Sandy really brought the idea of building resiliency into the mainstream of facility operation and design, NYSERDA has been requiring cogeneration systems funded through NYSERDA programs be capable of providing standby power to facilities since the Blackout of 2003.
Cogeneration has become a key potential part of such enhanced building “resiliency”. Aside from cost savings, one of cogeneration’s biggest assets is the ability to act as a standalone generator. As long as the cogeneration unit has a fuel supply, key building services like elevators and hallway lighting, fresh water pumps, and sometimes boilers can be supplied during utility outages.
There are some very significant considerations in integrating cogeneration units into standby power systems. First and foremost, cogeneration units are meant to operate as cogeneration units -their operating objective is to offset electrical and thermal baseloads in the facility on a continuous basis. They are simply not intended to be as “robust” as true standby generators and not intended as an alternative to any required standby or emergency generation systems with life or safety loads. The electrical loads added to a cogeneration standby power system must be carefully selected to ensure they will not overload the cogeneration units. Another key issue is the installation of “regenerative” elevator systems in new buildings or as replacements in existing buildings. Regenerative elevators can present a very serious problem for small cogeneration systems that are attempting to maintain power supply and load in an “islanded” standby power system in a building.
We have dealt with the considerations and requirements for cogeneration-based standby power systems since the start of NYSERDA requirements for standby power capability in funded cogeneration systems. We work closely with the building and key entities such as the elevator service company to design and implement effective standby power systems to enable basic comforts and services to continue during power outages.
Cogeneration, like other energy systems, takes a lot of paperwork to make it happen. While we try to be as digital as possible, a good project still needs the paperwork to make it happen. Frankly, it takes a lot less paper to carryout a good project than the paper that gets generated from one that does not go as well.
Our Design Documentation includes our detailed MEP drawings and the supporting specifications, usually in the “Master Spec” format, plus our system summary descriptions and sequences of operations. Experience has shown repeatedly that the better a project is documented in the design and bid/contract phases, the better it will go in the implementation phase. Details, such as submittal processing, simply make the project go smoother and set everyone’s expectations at the beginning.
Project commissioning is becoming a more common component; having an impartial third party reviewing the design and then verifying operation of each component and overall systems may seem like a unnecessary expense and in some very basic projects, this is true. However, commissioning has become an accepted and readily justified part of even relatively basic projects. Our design process and documentation will work with commissioning agents to support their role and ultimately facilitate completion of a successful project. Frankly, it can be more work for us in design and implementation to support commissioning, but it makes for a better project for the client and that is still the priority.
An alternative to the detailed design package process is the Request For Proposals (RFP) approach to project implementation. In the RFP process, the design package is prepared to schematic level with equipment selections and basic locations identified. The RFP solicitation is then sent out to potential respondents to obtain their proposals for implementing the project.
Bid solicitation for DSMEA projects is a process which provides the facility and owner with pricing for the project from qualified contractors and vendors. The bid process is undertaken to obtain competitive pricing for the project. Bid solicitation is undertaken once the design documents have been completed and are assembled into a bid package.
During the bidding process, DSMEA typically will provide contractors with whom we have previous experience for the kind of work being done (its not all just cogeneration after all). We support the bid process by conducting a pre-bid conference and site walk-through for all bidders, providing them familiarity with the project and the site and with a chance to go over questions they may have from the bid documents. While contractors are preparing their bids, DSMEA provides response to technical questions as they may come up.
Upon receiving all the bids, DSMEA will review them with the facility, comparing the bids to arrive at a recommended awardee with the facility. The bid evaluation process will often include a “leveling” phase wherein the bids are reviewed based on compliance with design intent including review and revision with bidders to ensure all bids are for the same scope. This minimizes differences in bid prices that may have resulted from different interpretation by bidders of the project design intent.
During the implementation phase of a project, DSMEA will provide oversight and support similar to the role of Owners Engineering Representative. Tasks typical to implementation oversight will include periodic attendance of project meetings and site inspections to verify work status and respond to requests for information. Review of submittals and review of requests for payment will be part of our scope during implementation as well, along with support for preparation and submission of permit applications and other project documents. The preparation and submission of interconnection applications for electrical and gas utility interconnection of cogeneration projects are key tasks that DSMEA will carry out.
DSMEA is not part of the daily project management or implementation -we do stress that contractors must have full time supervisory personnel on site for most projects to maintain coordination and management of the project.
As the project proceeds, where there is a commissioning agent involved, DSMEA will typically work with the commissioning agent to support their scope of service. The same is true of special inspection agents as required by the project.
Where applicable, DSMEA will provide reporting and other documentation to funding agencies such as NYSERDA.
Finally, as a project is completed, DSMEA will prepare punch lists for contractor closeout of the project and sign-off of the project completion documents where needed.
Cogeneration projects more than most benefit from on-going performance reporting. Any cogeneration project implemented through NSYERDA funding will include a Monitoring and Verification (M&V) system that provides hourly date to NYSERDA on key project performance indices such as electrical and thermal production, fuel consumption, and facility utilization of the outputs. This data provides the foundation for assessment of performance, but will not be enough by itself to show what kind of return on investment the facility is realizing each month. The NYSERDA M&V data documents the basic energy parameters but another level of reporting is needed to provide a clear, understandable answer to the most basic question “Am I getting my money’s worth out of the cogeneration system?”
DSMEA provides that additional layer of reporting for our cogeneration sites through Cost-Benefit Analysis Reporting (CBAR). We collect the NYSERDA data for each site at no greater than weekly intervals; this also ensures that problems with the NYSERDA data (failed sensors for example) do not go undetected for any length of time. We often see the data on a daily basis to make sure nothing unusual has happened such as cogeneration units being off line. DSMEA is not assuming responsibility for the detection and notification of such situations but we are adding another set of eyes to the monitoring process. Beyond the NYSERDA M&V data, we will also collect the monthly billing information for the site from the client, at least as long as it is reasonably available and provided. CBAR reports are compiled from the NYSERDA data and the billing data to estimate cost reductions achieved by the cogeneration during each billing period.
Surprisingly, this additional review and reporting is not done by many sites; our CBAR reports provide our client sites with the information they need to see how well their system is performing. This is really important for the site and for the other stake holders such as NYSERDA, the cogeneration service company, and DSMEA of course.