BEE Question-Bank Contributed by Dhanesh updated on Jan 2021

Duration: 3 HRS 
Max. Marks: 150

General instructions:
o Please check that this question paper contains 65 questions
o The question paper is divided into three sections
o All questions in all three sections are compulsory
o All parts of a question should be answered at one place

Section – I: OBJECTIVE TYPE Marks: 50 x 1 = 50
(i) Answer all 50 questions
(ii) Each question carries one mark

1.Which of the following is not a Primary Energy Source?

a) Oil b) Natural Gas c) Electricity d) Wood

2.Which of the following is a renewable energy source?

a) Bitumen b) Solar Energy c) Coal d) Natural Gas

3.Which of the following States in India does not have proven coal reserve?

a) Andhra Pradesh b) Madhya Pradesh c) Kerala d) West Bengal

4.At present the share of hydro power in the country’s total generated units is around

a) 20% b) 25% c) 30% d) 35%

5.Greenhouse effect refers to increase in

a)Global temperature. b) Carbon monoxide c) atmospheric pressure d) Greenery

6.The nodal agency for coordinating the energy conservation activities under EC act in India is 

a) Bureau of Indian Standards b) Bureau of Energy Efficiency
c) Bureau of Energy Education d) Bureau of Energy and Environment

7.X-Ray is a form of 
a. Chemical Energy
b. Radiant Energy
c. Thermal Energy
d. Potential Energy

8.Ratio of maximum demand to connected load is termed as:
a. Load factor
b. Power factor
c. Demand factor
d. Form factor

9.When heat is added or subtracted, resulting in a change of temperature is called as
a. Sensible heat
b. Latent heat
c. Specific heat
d. Heat capacity

10.The objective of energy management is 
a) To minimize energy costs
b) To minimize environmental effects
c) a & b 
d) None of the above

11.For calculating plant energy performance which of the following data is not required
a) Current year’s production
b) Reference year production
c) Reference year energy use
d) Capacity utilization

12.The simplest technique for scheduling of tasks and tracking the progress is
a) Gantt chart b) CPM c) PERT d) CUSUM

13.Moderation of chilled water temperature for process is 
a) Matching energy usage to requirement
b) Increasing system efficiency
c) None of the above
d) a & b

14.Which of the following is used to represent energy balance of a system?

a) Sankey Diagram 
b) Flow Chart 
c) Single line Diagram 
d) Block Diagram

15.Among the following, which is most important for carrying out a material balance

a)Temperature of Products 
b) Mass 
c ) Waste Quantity 
d) Pressure

16.In PV = nRT, Value of R is

a)0.008206 m3 atm / mole K 
b)0.8206 m3 atm / mole K
c)0.08206 m3 atm / mole K 
d)0.09206 m3 atm / mole K

17.Energy available in fuels is stored as
a)Heat Energy b) Chemical Energy c) Atomic Energy d) Explosive Energy

18.In continuous process which is considered for carrying out mass balance 

a) Material Flow b) Time c) Both a and b d) None of the above

19.Reactive Power is required for 
a. Inductive load
b. Resistive load
c. Capacitive load
d. All of the above

20.In a purely resistive circuit the reactive kVAR will be
a) less than 1 b) more than 1 c) zero d) one

21.Which one is the key element for successful Energy Management?
a) Top management support b) Planning c) Monitoring d) Training

22.Capital costs are the costs associated with 
a) Design
b) Installation & Commissioning of project
c) a & b 
d) Savings from project

23.What is the NPV of a project , (life 2 year) which requires an investment of Rs.50000 & yield Rs.30000 in the 1st year and Rs.40000/- in the next year, if the interest rate is 10%
a) 10330
b) (10330)
c) 20660
d) (30660)

24.Which is not a general practice of financing in-house energy management
a) From a central budget
b) Bank loan
c) Money from stock market
d) Hire purchase

25.The first step in a project development cycle is
a) Identify components of the project b) Implement the project c) arrange finance d) Training

26.For an investment which has a fluctuating savings over its project life which of these analysis would be the best option
a) Payback b) NPV c)ROI d) IRR

27.What is the future value of Rs.1000/- after 3 years if the interest rate is 10%?
a) 1610
b) 3221
c) 1331
d) 2420

28.If asset depreciation is considered, then tax cash flow would be 
a) Higher
b) Lower
c) No effect
d) None of these

29.ESCO stands for
a) Energy supply company b) Energy service company c) Energy standards company d) Energy sourcing company

30.Which of the following is not an external source of fund
a) Bank loans
b) Leasing arrangement
c) Revenue budget
d) Private Finance

31.Event in a project network diagram represents
a) Task
b) Milestone
c) a & b
d) none of the above

32. The essential elements of monitoring and targeting system is

a) Recording b) Reporting c) Controlling d) All the above

33. Which is not a green house gas
a) Methane b) Nitrous oxide c) Carbon di oxide d) Sulphur di oxide
34. If LPG has GCV of 12000 Kcal / kg, then 12 KWh is equivalent to --------kg LPG

a) 0.96 b) 0.86 c) 8.6 d) 86

35. Percentage share of different energy consumption in an industry can be best shown by a 

a) Pie Chart b) Bar Chart c) Line Diagram 

36. A mass balance for energy conservation does not consider which of the following
a) steam b) water c) raw materials d) lubricating oil
37. In the equation, Energy consumed = C + (M x Production) , where ‘C’ is

a) Variable energy consumption b) Fixed energy consumption
c) Specific energy Consumption d) None of the above

38. Based on the following Net present values, which of the projects is attractive for investment
a) –2199 b) + 23 c) 0 d) +13

39. While plotting a ‘CUSUM Chart’, it is observed that “CUSUM’ during previous month was 8, the same during this month will be

a) ? 8 b) ? 8 c) = 8 d) Can’t be said

40. Specific energy Consumption can be expressed in which of the following units.

a) Tone / Kwh b) KCal / Kg c) Kcal / Kwh d) None of the above

41. The Ozone layer in the atmosphere acts as an efficient filter for

a) X-Rays b) UV-A Rays c) UV-B Rays d) Intra red Rays

42. Which of the following does not damage ozone layer?

a) CFC b) CCl3 c) HCFC d) HFC

43. Which gas causes global warming among the following?

a) CFC b) SO2 c) O2 d) Argon 

44. Ozone has 
a) Three oxygen atoms b) Two oxygen atoms c) Two chlorine atoms d) Two bromine atoms
45. GHG emissions are presented in ------------ Units


46. The major source of electrical power generation in India is 
a) thermal b) Hydel c) Nuclear d) Wind

47. The quantity of heat required to raise 1 kg of a substance by 1oC is known as
a) sensible heat b) specific heat c) latent heat d) calorie

48. Matching energy use to requirement means providing 
a) just theoretical energy needed b) just the designers’ needs c) energy with minimum losses d) less than what is needed 

49. The internal rate of return is the discount rate for which the NPV is
a) Zero b) +ve c) –ve d) Less than 1

50. The monthly electricity bill for a plant is Rs. 10 lakhs and accounts for 38% of the total energy bill. The annual energy bill for the company
a) Rs. 315 lakhs b) Rs. 26 lakhs c) Rs. 38 lakhs d) Rs. 380 lakhs

Section - II: SHORT DESCRIPTIVE QUESTIONS Marks: 10 x 5 = 50

(i) Answer all Ten questions
(ii) Each question carries Five marks

1 What are the immediate term energy strategies recommended?

The immediate term energy strategies recommended are:
• Rationalizing the tariff structure of various energy products
• Optimum utilization of existing assets
• Efficiency in production systems and reduction in distribution losses, including those in traditional energy sources.
• Promoting R & D, transfer and use of technologies and practices for environmentally sound energy systems, including new and renewable energy sources.

2 A 3 ? AC Load draws 8 KW power at 400 V supply voltage and 15 A line current. Calculate the power factor of the load.

Supply Voltage of the System (VL) = 400
Line Current (IL) -=15 A
Apparent Power = 3 x VL x IL 

= 3 x 0.400 x 15 

= 10.392 KVA

Active Power = 3 x VL x IL x (Cos ?) KW 

Given, active power of the Load = 8 KW

Hence, 10.392 COS ? = 8 KW

3 How benchmarking of energy consumption internally and externally may be useful.

Benchmarking of energy consumption internally and externally (historical/trend analysis) are two powerful tools for performance assessment and logical evolution of avenues for improvement. Historical data well documented helps to bring out energy consumption and cost trends month-wise/day-wise trend analysis of energy consumption, cost, relevant production features, specific energy consumption help to understand effects of capacity utilization on energy use efficiency and costs on a broader scale.
4 Why steam is used as a popular mode of conveying energy?

The following characteristics of steam make it very popular and useful to convey energy in the industries.

• High Specific heat and latent heat
• High heat transfer coefficient
• Easy to control and distribute
• Cheap and inert

5 In a chlora-alkali plant, the inlet brine concentration to cell house is 300 gpl and the outlet concentration is 260 gpl. If 3 MT Salt is added per hour, find out the brine flow rate to the Cell House.

Answer :
Inlet concentration of brine = 300 gpl
Outlet concentration of brine = 260 gpl
Salt consumption per litre of Flow = (300-260) gm
= 40 gm = 0.040 Kg
For 3 MT/hr Salt consumption, flows = 3 x 1000 Kg /hr
0.040 Kg/lit

= 75,080 Lit/hr
= 75 m3/hr

6 What are the duties and responsibilities (five each) of Energy Manager as per the Energy Conservation Act 2001?


• Prepare an annual activity plan and present to management concerning financially attractive investments to reduce energy costs
• Establish an energy conservation cell within the firm with management’s consent about the mandate and task of the cell.
• Initiate activities to improve monitoring and process control to reduce energy costs.
• Analyze equipment performance with respect to energy efficiency
• Ensure proper functioning and calibration of instrumentation required to assess level of energy consumption directly or indirectly.


• Report to BEE and State level Designated Agency once a year the information with regard to the energy consumed and action taken on the recommendation of the accredited energy auditor, as per BEE Format.
• Establish an improved data recording, collection and analysis system to keep track of energy consumption.
• Provide support to Accredited Energy Audit Firm retained by the company for the conduct of energy audit
• Provide information to BEE as demanded in the Act, and with respect to the tasks given by a mandate, and the job description.
• Prepare a scheme for efficient use of energy and its conservation and implement such scheme keeping in view of the economic stability of the investment in such form and manner as may be provided in the regulations of the Energy Conservation Act.

7 Explain Net Prevent Value and how NPV is calculated.

Net Present Value:
The net present value (NPV) of a project is equal to the sum of the present values of all the cash flows associated with it. 
Where NPV = Net Present Value
CF t = Cash flow occurring at the end of year ‘ t ‘ (t = 0,1, ….n)
n = Life of the project
k = Discount rate
The discount rate (k) employed for evaluating the present value of the expected future cash flows should reflect the risk of the project.

8 Define project and mention various steps involved in Project Management

A project is a temporary endeavor undertaken to create a unique product or service. A project is temporary in that there is a defined start (the decision to proceed) and a defined end (the achievement of the goals and objectives)

Steps in Project Management:

The various steps in a project management are:

a) Project definition and scope
b) Technical Design
c) Financing
d) Contracting
e) Implementation
Performance Monitoring

9 Calculate fixed energy consumption for a rolling mill consuming 3,00,000 units electricity to produce 500 MT product per month and having specific energy consumption of 500 Kwh/MT.

Total energy consumed = Fixed Energy Consumption + (Specific Energy 
Consumption x Production)
Fixed energy consumption = Total energy consumed – (Specific energy 
consumption x Production)
Total Energy Consumption = 3,00,000 Kwh
Specific energy Consumption = 500 Kwh / MT
Total Production = 500 Mt
Fixed Energy Consumption = 300000 – (500 x 500)
= 5000 Units

10 Explain briefly about Emission Trading?

Article 17 of the Kyoto protocol opens up for emissions trading between countries that have made commitments to reduce greenhouse gas emissions. The countries have option to delegate this right of emissions trading to companies or other organizations.

In a system for emissions trading, the total amount of emissions permitted is pre-defined. The corresponding emissions allowances are then issued to the emitting installations through auction or issued freely. Through trading, installations with low costs for reductions are stimulated to make reductions and sell their surplus of emissions allowances to organizations where reductions are more expensive. Both the selling and buying company wins on this flexibility that trades offers with positive effects on economy, resource efficiency and climate. The environmental advantage is that one knows, in advance, the amount of greenhouse gases that will be emitted. The economical advantage is that the reductions are done where the reduction costs are the lowest. The system allows for a cost effective way to reach a pre-defined target and stimulates environmental technology development. 

Section - III: LONG DESCRIPTIVE QUESTIONS Marks: 5 x 10 = 50

(i) Answer all Five questions
(ii) Each question carries Ten marks

1 Explain in detail the difference between Energy Conservation and Energy efficiency and its relevance

Energy Conservation and Energy Efficiency are separate, but related concepts. Energy conservation is achieved when growth of energy consumption is reduced, measured in physical terms. Energy Conservation can, therefore, be the result of several processes or developments, such as productivity increase or technological progress. On the other hand Energy efficiency is achieved when energy intensity in a specific product, process or area of production or consumption is reduced without affecting output consumption or comfort levels.
Promotion of energy efficiency will contribute to energy conservation and is therefore an integral part of energy conservation promotional policies.

Energy efficiency is often viewed as a resource option like coal, oil or natural gas. Energy efficiency provides additional economic value by preserving the resource base and reducing pollution. For example, replacing traditional light bulbs with Compact Fluorescent Lamps (CFLs) will use only ¼ of the energy to light a room.

Apart from the economic benefits, energy conservation and energy efficiency measures would assist in controlling the CO2 emission.

2 Explain in detail the methodology for conducting a detailed energy audit.

A detailed energy audit is carried out in three phases:
a) Pre-audit phase
b) Audit phase &
c) Post Audit phase

Pre Audit Phase:
A structured methodology to carryout an energy audit is necessary for efficient working. An initial study of the site is essential, which will give an energy auditor an opportunity to meet the personnel concerned to familiarize the site and assess the procedures necessary to carry out the energy audit. The main aim of this visits are:

• To identify the main energy consuming areas/plant items to be surveyed during the audit.
• To identify any existing instrumentation/additional metering required
• To decide whether any meters will have to be installed prior to the audit e.g. Kwh steam, oil or gas meters.
• To identify the instrumentation required for carrying out the audit

Audit Phase:
As a first step during the audit phase, Energy Auditor would collect the base line data, preparation of process flow charts etc. The monitoring and measurement will be next stage. As per the field observations, detailed trials may be conducted for selected energy guzzlers in the plant. Once all the operating data and design data and other operational practices are collected/observed, detailed analysis of the data will have to be done. Based on the analyses, Energy Conservation opportunities may be developed and the economic viability of the options has to be established. The study has to properly documented and the suggestions and findings are to be presented to the top management

Post-Audit Phase:
In post audit phase the energy Auditor/Engineer may assist and implement the energy conservation recommendation measures and monitor the performance.

3 During a ESP performance evaluation study, the inlet gas stream to ESP is 289920NM3/hr and the dust loading is 5500 mg/ NM3. The outlet gas stream from ESP is 301100M3/hr and the dust loading is 110 mg/NM3. How much fly ash is collected in the system?

Based on Mass balance,

Inlet gas stream dust = Outlet Gas stream dust + Fly ash

a) Inlet gas stream flow = 289920 NM3/hr
Dust Concentration = 5500 mg/NM3
Inlet dust quantity = 289920 x 5500
= 1594.50 kg/hr

b) Outlet dust quantity = 301100 (NM3/hr) x 110 (mg/NM3) x 1 
= 33.12 kg/hr
c) Fly Ash = Inlet gas stream dust – Outlet gas stream dust
= 1594.56 – 33.12 = 1561.44 kg/hr 

4 Explain the following stating the advantages and limitations if any
a) Simple Pay Back Period
b) Return on Investment
c) Internal rate of return

Simple Payback Period (SPP) represents, as a first approximation: the time (number of years) required to recover the initial investment (First Cost),considering only the Net Annual Saving:

The simple payback period is usually calculated as follows:

Simple payback period 
A widely used investment criterion, the payback period seems to offer the following advantages:
• It is simple, both in concept and application. Obviously a shorter payback generally indicates a more attractive investment. It does not use tedious calculations.
• It favours projects, which generate substantial cash inflows in earlier years, and discriminates against projects, which bring substantial cash inflows in later years but not in earlier years.
• It fails to consider the time value of money. 
• It ignores cash flows beyond the payback period. This leads to discrimination against projects that generate substantial cash inflows in later years.
Return on Investment (ROI)
ROI expresses the “annual return” from the project as a percentage of capital cost. The annual return takes into account the cash flows over the project life and the discount rate by converting the total present value of ongoing cash flows to an equivalent annual amount over the life of the project, which can then be compared to the capital cost. 
• It does not take into account the time value of money
• It does not account for the variable nature of annual net cash inflows.
Internal Rate of Return:
This method calculates the rate of return that the investment is expected to yield. The internal rate of return (IRR) method expresses each investment alternative in terms of a rate of return (a compound interest rate).
popular discounted cash flow method, the internal rate of return criterion has several advantages:
• It takes into account the time value of money
• It considers the cash flow stream in its entirety
• It makes sense to businessmen who prefer to think in terms of rate of return and find an absolute quantity, like net present value, somewhat difficult to work with.
The internal rate of return figure cannot distinguish between lending and borrowing and hence a high internal rate of return need not necessarily be a desirable feature.

5 Explain in detail about Ozone Layer depletion process ad its various effects

Ozone is highly reactive and easily broken down by man-made chlorine and bromine compounds. These compounds are found to be most responsible for most of ozone layer depletion.

The ozone depletion process begins when CFCs (used in refrigerator and air conditioners) and other ozone depleting substances (ODS) are emitted into the atmosphere. Winds efficiently mix and evenly distribute the ODS in the troposphere. These ODS compounds do not dissolve in rain, are extremely stable, and have a long life span. After several years, they reach the stratosphere by diffusion.

Strong UV light breaks apart the ODS molecules. CFCs, HCFCs, carbon tetrachloride, methyl chloroform release chlorine atoms, and halons and methyl bromide release bromine atoms. It is the chlorine and bromine atom that actually destroys ozone, not the intact ODS molecule. It is estimated that one chlorine atom can destroy from 10,000 to 100,000 ozone molecules before it is finally removed from the stratosphere. 

Effects on Human and Animal Health :

Increased penetration of solar UV-B radiation is likely to have high impact on human health with potential risks of eye diseases, skin cancer and infectious diseases.

Effects on Terrestrial Plants :

In forests and grasslands, increased radiation is likely to change species composition thus altering the bio-diversity in different ecosystems. It could also affect the plant community indirectly resulting in changes in plant form, secondary metabolism, etc.

Effects pm Aquatic Ecosystems:

High levels of radiation exposure in tropics and subtropics may affect the distribution of phytoplanktons, which form the foundation of aquatic food webs. It can also cause damage to early development stages of fish, shrimp, crab, amphibians and other animals, the most severe effects being decreased reproductive capacity and impaired larval development.

Effects on Bio-geo-chemical Cycles : Increased solar UV radiation could affect terrestrial and aquatic bio-geo-chemical cycles thus altering both sources and sinks of greenhouse and important trace gases, e.g. carbon dioxide (CO2),carbon monoxide (CO),carbonyl sulfide (COS),etc. These changes would contribute to biosphere-atmosphere feedbacks responsible for the atmosphere build-up of these greenhouse gases.

Effects on Air-Quality : Reduction of stratospheric ozone and increased penetration of UV-B radiation result in higher photo dissociation rates of key trace gases that control the chemical reactivity of the troposphere. This can increase both production and destruction of ozone and related oxidants such as hydrogen peroxide, which are known to have adverse effects on human health, terrestrial plants and outdoor materials.