Energy Recovery in 最小值nesota 商业 and Institutional Buildings (CLOSED)

Energy recovery ventilation systems exchange energy between the outgoing exhaust air and the incoming outdoor (ventilation) air to reduce heating and cooling energy while meeting ventilation requirements. 按设计操作时, it is possible for ERVs to use 10 to 100 times less energy than conventional heating and cooling systems, resulting in up to 80% energy savings on ventilation loads.

Despite their substantial energy efficiency potential, studies on as-operated energy recovery units are few and expectations have been tempered by real world observations — there is anecdotal evidence suggesting that as-operated performance of ERVs may not live up to expectations.

This project characterized ERVs in 最小值nesota commercial and institutional buildings, studied a representative sample ERVs in detail, and characterized improved ERV performance.
 

结果

描述
The research team analyzed data on 402 ERVs from 134 different buildings to understand basic system demographics. The analysis showed that the majority of buildings with ERVs also have multiple air handling systems, 多种能量回收系统, 和几个相同类型的erv. 然而, only a fraction of ventilation air is typically served by energy recovery, 特别是在机构建筑中. 

ERVs in 最小值nesota are most commonly found in institutional buildings, 通常是K-12学校, as well as a variety of commercial building types with high ventilation loads. In both commercial and industrial buildings, the importance of large units to state-wide savings is striking — the top 25% of units are responsible for conditioning over 13 times the amount of ventilation air as the bottom quarter of units. 

重新调试节省的能源
The research team selected nine ERVs for recommissioning, 结果总共节省了17美元,168, 或者说能量回收率提高了42%. 

With respect to energy savings and outside air temperature, 至少, an ERV should be activated between 0ᵒF and 45ᵒF in order to realize between 60% and 80% of potential savings, and also above 80ᵒF to achieve peak cooling load reduction.

ERV系统中的问题 
The project team identified and documented 75 different issues among the nine ERVs in the study. While the types of issues and their impact varied widely, they can be sorted into 11 different categories, 如下图所示. 

靠谱的外围竞猜app one third of the issues had major energy impacts, 三分之一只有轻微的能量影响, and about one third had no energy impact beyond diminishing the perception and expectations of ERVs. The energy and cost penalties of the encountered issues are summarized in the table below.

建议

调试新系统
The persistence of dysfunctional ERVs as part of normal operations indicates a need for system installations to be validated immediately. Fifty percent of the found savings discovered would have been identified during a robust initial commissioning process.

改善现有制度
ERV problems often go unnoticed because there are usually no obvious operational implications. The majority of energy penalties that were found as a part of this project can be discovered and avoided staff are able to 1) identify when an ERV should be running and 2) assess whether an ERV is running. This does not necessarily require a full recommissioning effort, but dedicated recommissioning may be needed to achieve additional savings opportunities.

加深对ERV运作的了解
与部件故障有关的错误, 操作符覆盖, and installation account for 75% of the lost energy recovery, and are largely due to unfamiliarity among operations staff and controls technicians and the absence of system feedback from poorly functioning ERVs. 幸运的是, these mistakes can be easily corrected by commissioning new units to ensure that they function properly from the start, and through better training and clear communication among design engineers, 承包商, 委托代理, 建筑业主.