Voltage unbalance degrades performance and shortens the life of a three-phase motor. It causes phase current unbalance far out of proportion to the voltage unbalance. Unbalanced currents lead to torque pulsations, increased vibrations and mechanical stresses, increased losses, and motor overheating, which results in a shorter winding insulation life.
To find out readers’ opinions about where solar products stand in today’s market, a brief, informal online survey was conducted on The NEWS Website. Survey respondents in this case do feel solar is taking hold in the residential sector.
Scenario: Single stage residential
cooling equipment. Homeowner complains that humidity is too high at their
desired thermostat setting. Actions: You think this is too easy. Probably a system-related
problem (dirty filter, low charge, dirty condenser; the usual stuff). But you
also realize that it’s been a little cooler than most summers.
Outdoor air brought into a building can be expensive to temper and, if not properly conditioned, can cause humidity problems for the building. Designers are increasingly finding that using dedicated outdoor air systems (DOAS) allows them to comply with ASHRAE 62.1 with an energy efficient and easily verifiable design.
The U.S. Department of Energy (DOE) has actively supported cost-shared combined heat and power (CHP) R&D and demonstration projects. This article showcases four successful CHP demonstration projects, and illustrates its broad applicability across industrial, commercial, and institutional facilities.
The U.S. Department of Energy’s (DOE’s) Industrial Technologies Program (ITP) has identified combined heat and power (CHP) as one of the most important opportunities available today for increasing energy efficiency and reducing emissions. This article explains CHP technology uses and benefits.
As heat densities and cooling costs rise, data center professionals are looking for more efficient cooling solutions. A cold aisle containment retrofit can be implemented easily and quickly, carries a payback time from weeks to a few months, and can reduce cooling related energy costs by as much as 30 percent.
Unfortunately, many fleets simply take a reactive approach to vehicle maintenance. In a widely distributed fleet, that could mean costly repairs, not to mention vehicle downtime. Fleet managers need to be able to monitor and collect data on the “health” of their vehicles to fix problems early and reduce costs.
The
Mechanical Contractors Education and Research Foundation recently released a
new study that describes green building technologies being
implemented in Europe that could be used in the United States, especially
chilled beams and active or dynamic façades.
The St.
Cloud (Minn.) Municipal Athletic Center (MAC) found a way to go green and save
taxpayer dollars in the process. With the installation of a new GeoExchange
system, the MAC is using the earth to maintain the arena ice and heat the
facility, saving electricity and gas as well as reducing greenhouse gas
emissions.