ESET 444 LATEST SET FINAL EXAM 2025

In addition to charging for peak demand, some utilities charge for kvars. What does the "R" stand for in "kvar?" - Correct Answer-Reactive An electric motor has input power rating of 250 kW. If the output power at fully rated load is 200 kW, what is the efficiency of the motor? - Correct Answer-80% Why could the energy content of a fuel have a different value reported in the US compared to Europe? - Correct Answer-The US typically uses higher heating value, which includes the energy contained in water vapour. Europe typically uses lower heating value, which does not include the heat associated with water changing state. A factory uses 3000 therms / 8330 cubic metres of natural gas each month. The gas costs 72 cents per therm / 26 cents per cubic metre. The energy value of the gas is 10.5 kWh per cubic metre. A kWh of electricity costs 7c. Should the site switch from natural gas to electricity, assuming that the efficiency remains the same? - Correct Answer-No, the same energy value of electricity costs more Which term describes a fuel that contains energy source that has not undergone any conversion - Correct Answer-Primary On a particular day the temperature monitoring system registered 7 cooling degree days. What does this mean? - Correct Answer-The mean temperature was 7 degrees above the base temperature In both the US customary and SI systems, electricity is expressed using which of the following terms? - Correct Answer-Watts (kilowatts) Which unit of measurement is generally used to measure energy content? - Correct Answer-British Thermal Units (US) joules (SI) A resistance of 500 ohms has a measured voltage drop of 120v. How much power is driving the current? - Correct Answer-28.8 watts A resistance of 100 ohms has 4 amps flowing through it. What is the voltage drop across the resistance? - Correct Answer-400 volts ESET 444 ESET 444 When making efficiency improvements, passive and active efficiency measures should always be followed by which of the following in order to sustain savings? - Correct Answer-Monitoring Installing occupancy and light-level sensors and implementing variable frequency drives in motors are examples of which type of efficiency measure? - Correct Answer-Active Which of the following is the name for an analysis of a building's energy use where opportunities for reducing energy consumption are identified and prioritized? - Correct Answer-Energy audit How much energy efficiency improvement can be achieved with current technologies? - Correct Answer-Up to 30% Replacing existing equipment with lower consumption devices, fixing leaks and adding insulation are examples of which type of efficiency measure? - Correct Answer-Passive Why is energy efficiency at the point of use the quickest, cleanest, most effective solution to the energy dilemma? - Correct Answer-( )Because due to transmission and generation losses, 300 units of primary energy are required to provide 100 units of end-user electricity. Hence saving energy at the point of use is more effective than building a new power plant with double the efficiency ( )Because the cleanest unit of energy is a unit of energy that wasn't produced and used ( )Because energy efficiency solutions are available now ( )Because energy projects are low risk and outperform many other investments (x)All of the above ← Correct answer Energy efficiency can be defined as: - Correct Answer-Reducing the amount of energy used while maintaining outcomes: doing more with less What is the energy dilemma? - Correct Answer-Energy demand is forecast to double, while emissions have to be cut by half to avoid dramatic climate change What percentage of energy consumption is used by industry, residences and tertiary buildings? - Correct Answer-72% "You can't manage what you don't measure". Which of the following helps you overcome this issue regarding energy? - Correct Answer-Energy management software The purpose of a building control system is to measure environmental data (E.g. temperature, humidity, pressure, or flow rate), compare that data against predetermined standards and initiate a change in order to change or maintain current environmental conditions. - Correct Answer-True ESET 444 ESET 444 A simple ______________ is defined as one input to a controller housing the control logic, which provides an output to one controlled device. - Correct Answer-Control loop What provides data to the controller? - Correct Answer-Input devices such as sensors or contact closures Which control system component interprets the input according to its control logic? - Correct Answer-Controller Which control system component is activated in order to change or maintain environmental conditions? - Correct Answer-Controlled device This is the type of control loop where the output has no effect on the controlling variable - Correct Answer-Open Another name for a cascade control loop is: - Correct Answer-Reset control loop This is the type of control loop where the controlling variable is affected by the actions of the controlled device upon the controlled variable. - Correct Answer-Closed This is the type of control loop used to modify the performance of closed control loops when required - Correct Answer-Cascading HVAC includes which processes? - Correct Answer-Heating, cooling, humidifying, dehumidifying, cleaning, ventilating and air movement An HVAC all-air system brings in outdoor air for ventilation, provides treated supply air to the conditioned space, removes return air from the space, and vents relief or exhaust air to the outside - Correct Answer True A typical configuration for a split system is - Correct Answer-Compressor and condenser outside the building on the ground or roof; evaporator and air handlers inside the building Zoning is used to - Correct Answer-identify spaces in a building expected to have similar thermal loads Pressure balancing is important because: - Correct Answer-( )If an exhaust system takes are out of a space, and the air is not replaced by make up air, the pressure inside the building will be different to the outside pressure ( )If a building has significant negative pressure it can be difficult to open doors, and infiltration of unconditioned air can create drafts. ESET 444 ESET 444 ( )If a building has significant positive pressure indoor humidity can be driven into wall spaces and encourage growth of molds (x)All of these answers What happens to return air from an office space? - Correct Answer-It may be mixed with outside air and fed back to the space, to reduce the energy required to treat outdoor air Which of the following is NOT an advantage of an all-air HVAC system? - Correct Answer-Easy to ensure air balancing In an all-air system, a lot of energy is spent not on heating or cooling, but on moving the air - with considerable energy consumed by fans. - Correct Answer-True All air systems provide cold supply air to the conditioned space. The system usually includes supplementary refrigeration sources within the zones for additional cooling when required. Heating may be provided by the same supply airstream, or by terminal devices within a zone. - Correct Answer-False A unitary system or packaged unit contains all the components of the air-conditioning system in a single enclosure. Which of the following is NOT an advantage of a packaged unit: - Correct Answer-Step controls provide flexibility in temperature and humidity control If a 50 kW motor runs for 4 hours what would the demand be? - Correct Answer-50 kW If a 150 kW motor runs for 0.5 hours what would the consumption be? - Correct Answer 75 kWh The simplest form of energy pricing is the Block Rate where a customer pays a single price per unit for all energy consumed during the month. - Correct Answer-False When prices vary based on the time of year it is called which of the following? - Correct Answer-Seasonal rates A facility consumed 50,000 cubic meters of gas during a 30 day billing period. The rate structure uses the following block sizes defined in cubic meters per day: The first 100 cubic meters per day are charged at 18 cents per cubic meter The next 300 cubic meters per day are charged at 14 cents per cubic meter The next 600 cubic meters per day are charged at 10 cents per cubic meter The next 1,500 cubic meters per day are charged at 7.5 cents per cubic meter All remaining volume is charged at 3.5 cents per cubic meter What will the energy charge be for this billing period? - Correct Answer-$5,100.00 ESET 444 ESET 444 A facility incurred a peak demand of 600 kW. The site consumed 250,000 kWh during a 30 day billing period. The first 300 kWh per kW of peak demand are charged at 6.5 cents per kWh All remaining kWh are charged at 3.8 cents per kWh Calculate the energy charge. - Correct Answer-€14,360.00 The most common form of time-of-use pricing is a 2 part definition with on-peak and off peak. - Correct Answer-True On-peak refers to periods of relatively ___________ demand. - Correct Answer-High A time of use rate structure includes the following conditions Monday - Friday, 10 AM - 8 PM, 8.9c per kWh Monday - Friday, 8 PM - 10 AM, 4.3c per kWh Saturday and Sunday, 4.3c per kWh A facility consumed 400,000 kWh during peak periods, and 250,000 kWh during off peak periods. How much could they reduce their energy charge if they shift 80,000 kWh from peak to off-peak? - Correct Answer-$3,680.00 Shoulder periods are the times between On-Peak and Off-Peak periods, and exist to allow more pricing options. - Correct Answer-True The customer service charge is - Correct Answer-A fixed monthly charge based on the costs associated with connecting a customer to the company's distribution system Multiplying the energy consumption by the price per kWh will give you the - Correct Answer-Energy cost Real-time pricing response is when a customer - Correct Answer-Uses a generator to produce its own power for high price periods The demand charge is - Correct Answer-The portion of the bill where utility companies charge for having the capacity and infrastructure available to meet the peak utilization during the billing period Setting a new peak demand can affect both the demand charge for the month the peak is set as well as the bill for the following year. - Correct Answer-True Which of the following factors may have an impact on demand charges? - Correct Answer-( )Monthly peak demand ( )Subscribed power (x)All of the above ( )Price ESET 444 ESET 444 The energy charge is - Correct Answer-The portion of the bill based on total energy (kWh) consumed during the billing month and calculated under the applicable rate schedule Customers on Real Time Pricing rates have the potential for considerable savings if they can move energy from high price periods to low price periods, or reduce energy use during high price periods. - Correct Answer-True The demand ratchet is - Correct Answer-A charge based on previous peak demand to cover the cost of having capacity and infrastructure available at any time The fuel cost is - Correct Answer-A surcharge for the cost of fossil fuels When attempting to ensure a secure environment, always use factory default passwords in network devices, like UPS systems. - Correct Answer-False _____ are the weakest link in any security plan. - Correct Answer-People A firewall is a mechanism in which a controlled barrier is used to control network traffic into, and out of, an organizational intranet. - Correct Answer-True A simple firewall is: - Correct Answer-( )Set up to restrict all external access and only allow services originating from the inside. ( )Restricts connection requests from the outside. ( )Often used by people with home or small business cable or DSL routers. (x)All of the above. In the DMZ architecture, there are ______________ firewalls. - Correct Answer-two Authentication is ____________. - Correct Answer-the action of verifying the identity of a user The cost of security in an enterprise can be measured not just in dollars, but also in complexity, time and efficiency. - Correct Answer-True In order to thwart attack and avoid a security breach, data center professionals should: - Correct Answer-( )Know the network ( )Understand different threats ( )Take steps to ensure physical security (x)All of the above The internal intranet is referred to as the _____ side and the external Internet as the _____ side. - Correct Answer-trusted, untrusted ESET 444 ESET 444 Doing port lockdown by turning off services, _______. - Correct Answer-reduces the exposure to attackers, worms and Trojan viruses This system keeps supply air always at the same temperature, and delivers more or less air as required to maintain or change the temperature in the space - Correct Answer-Variable air volume This system always delivers the same airflow but the air may be hotter or colder as required to maintain or change the temperature in the space - Correct Answer-Constant volume How can a single-duct system be divided into zones with different thermal requirements? - Correct Answer-Either reheat method or VAV method could be used An air-side economizer is used when: - Correct Answer-The enthalpy of outdoor air is lower than that of the return air. The outdoor air is then used to provide free c