Energy Conservation

Energy Conservation Energy Management

Role of an energy manager 

Assess  



Analyse 



On technical improvements

Advertise 



Energy requirements

Advise 



Current energy demand Energy audit

Ways to save energy

Account 

For energy consumption

Assess energy demand 

Keep records  Consumption  Time of readings  Temperature  Other factors affecting demand  



Weekday/weekend Special events

Frequency of readings  

Weekly Daily

Energy Audit 

Feasibility study 



Aim 







Establish and quantify energy flows into and within a building or organisation Identify viable and cost effective energy saving measures Enhance operating efficiency and reduce maintenance costs Establish a baseline energy consumption

Process   

Collect data from energy invoices and meters Surveys of plant, equipment and buildings Collect information from managers and other staff

Auditing process 

Identify energy management opportunities 

Can be ‘no cost’ or ‘low cost’ measures   

Change an energy tariff Change an energy supplier Reschedule production activities • Preferential tariffs

  

Adjust existing controls to match requirements Implement ‘good housekeeping’ policies Invest in small capital items • Thermostats & time switches

Who does energy audits? Can be undertaken internally – energy manager  Specialist energy consultants  Energy service companies 

 



 

Performance contracts Guarantee organisations energy cost savings in return for a fee Main interest is in installing and managing their recommended plant May arrange finance of projects Vested interest

Why is energy wasted? 

Poorly designed buildings and installations  

Insufficient insulation Undersized ventilation ducts



Inadequate control systems  Poor control settings  Inefficient plant operation  



Out of date technology Poor maintenance

Poor operating and working practices

Different types of energy audit  According

to level of detail and depth of

analysis  Preliminary  Targeted

 Comprehensive

Preliminary audit



How much energy is being consumed  What type of energy  Performance of facility compared with similar facilities  Characteristic performance of building

Preliminary energy audit  

Identification of potential areas of energy saving Financial energy audits



Collect data 





Establish quantity and cost of each form of energy Data from energy invoices and meters for previous year

Analyse data  Present data  Establish priorities  Make recommendations

Targeted energy audit  Provide

data and analysis on specific targeted projects 

e.g. heating of one building or lighting

 Detailed

survey of target area  Analysis of energy flows and costs  Recommendations for action

Comprehensive energy audits 

Similar to preliminary audits but in far more detail  Detailed data on energy flows into and within organisation or facility 

 





 

Often requires use of sub-metering to accurately determine component energy flows Or estimate energy use (Plant power output (kWh)/efficiency of plant) *operating hours per year Use of thermal imaging May use complex energy simulation software

Detailed energy survey Energy project implementation plans

Collect data 

Build up picture of pattern of energy consumption and cost from energy invoices    



Collect geographic data  



Location, altitude, orientation Weather data, degree day data

Manufacturing data (if appropriate) 



All invoices for relevant time period Delivery notes for oil, solid fuel, LPG Identify estimated meter readings – check with previous years Inadequate/unavailable invoices – contact utility company/fuel supplier

Production output

Check data for anomalies  

Small building using more energy than larger one High energy use at night when unoccupied

Understanding invoices: electricity   

Date of meter reading Monthly standing charge Present and previous meter reading  



Charges for each rate 





For every kW of the peak power demand during the month Penalise users make heavy demands during peak periods

Supply capacity – annual maximum demand 



Some tariffs have a higher unit charge for first 1000 kWh

Monthly maximum demand charge 



Daytime – peak rate Night time – off-peak rate

Monthly charge

Total cost + VAT

Gas invoices 

   

Much less complicated than electricity Date of meter reading or estimate Calorific value of gas Present and previous meter readings Amount of gas used 

ft3, kWh or therms



Unit price per kWh  Standing charge 



Monthly or quarterly

Total cost + VAT

Other fuels 

Fuel oil 

Measured by volume • Varies with temperature corrected to standard condition of 15.50C

   



Date of delivery Unit cost per standard litre Calorific value (?) Total cost + VAT

Solid fuel    

Weight delivered Date of delivery Total cost + VAT No calorific value

Analysing energy records  Key

variables  Heating    

External temperature - dominant Wind speed ) Humidity )