Low-Lift Cooling Technology Option Set
Cooling Systems: Set of Advanced Cooling Technologies vs. Conventional
A set of five technologies based on low-lift vapor compression cooling equipment assembled by Pacific Northwest National Laboratory (PNNL) under a single name.
This is a technology option set first proposed by Pacific Northwest National Laboratory (PNNL) in 2007 in as part of DOE’s effort to achieve net Zero Energy Buildings in the commercial sector. It is actually a set of five strategies, with low-lift cooling central to its success. The five strategies are:
1. Peak-load shifting by means of active or passive thermal energy storage (TES)
2. Dedicated outdoor air supply with enthalpy heat recovery from exhaust air.
3. Radiant heating and cooling panels or floor system.
4. Low-lift vapor compression cooling equipment.
5. Advanced controls at the HVAC equipment and HVAC system (supervisory) levels.
The strategy is built with existing commercially –available equipment, but as of the fall of 2011, no one is offering this as an assembled package. The work on this so far has been with modeling. The results look promising, with energy savings as high as 74% in the right application. PNNL is preparing to do field studies – scoping out the project and seeking funding and test locations.
A note of caution, however: not all chillers can easily accept low-lift conditions. For example, some large chillers cannot operate below 30% of maximum flow. Therefore, this strategy requires a good understanding of the technologies being employed.
Energy Savings: 42%
Energy Savings Rating:
Limited Assessment What's this?
|1||Concept not validated||Claims of energy savings may not be credible due to lack of documentation or validation by unbiased experts.|
|2||Concept validated:||An unbiased expert has validated efficiency concepts through technical review and calculations based on engineering principles.|
|3||Limited assessment||An unbiased expert has measured technology characteristics and factors of energy use through one or more tests in typical applications with a clear baseline. |
|4||Extensive assessment||Additional testing in relevant applications and environments has increased knowledge of performance across a broad range of products, applications, and system conditions. |
|5||Comprehensive analysis||Results of lab and field tests have been used to develop methods for reliable prediction of performance across the range of intended applications.|
|6||Approved measure||Protocols for technology application are established and approved.|
Simple Payback is one tool used to estimate the cost-effectiveness of a proposed investment, such as the investment in an energy efficient technology. Simple payback indicates how many years it will take for the initial investment to "pay itself back." The basic formula for calculating a simple payback is:
Simple Payback = Incremental First Cost / Annual Savings
The Incremental Cost is determined by subtracting the Baseline First Cost from the Measure First Cost.
For New Construction, the Baseline First Cost is the cost to purchase the standard practice technology. The Measure First Cost is the cost of the alternative, more energy efficienct technology. Installation costs are not included, as it is assumed that installation costs are approximately the same for the Baseline and the Emerging Technology.
For Retrofit scenarios, the Baseline First Cost is $0, since the baseline scenario is to leave the existing equipment in place. The Emerging Technology First Cost is the Measure First Cost plus Installation Cost (the cost of the replacement technology, plus the labor cost to install it). Retrofit scenarios generally have a higher First Cost and longer Simple Paybacks than New Construction scenarios.
Simple Paybacks are called "simple" because they do not include details such as the time value of money or inflation, and often do not include operations and maintenance (O&M) costs or end-of-life disposal costs. However, they can still provide a powerful tool for a quick assessment of a proposed measure. These paybacks are rough estimates based upon best available data, and should be treated with caution. For major financial decisions, it is suggested that a full Lifecycle Cost Analysis be performed which includes the unique details of your situation.
The energy savings estimates are based upon an electric rate of $.09/kWh, and are calculated by comparing the range of estimated energy savings to the baseline energy use. For most technologies, this results in "Typical," "Fast" and "Slow" payback estimates, corresponding with the "Typical," "High" and "Low" estimates of energy savings, respectively.