building management system companies don't know their clients

Building management system companies don't know their clients !

What do I mean ? - I mean that they sell commodities, just as an electricity company sells kWh or a Gas company sells gas and Grundfos or ABB sell pumps, and Weissmann, Hoval, Carrier and Hitachi sell boilers and chillers.
Energy Companies manage by numbers

So what do we mean commodity - a commodity is by nature interchangeable and obviously (and problematically) many control systems are not.

 This is strange, they are completely interchangeable when you buy them (lets face it, they can all read inputs, drive outputs, do a bit of very slow real time control and interact with a network via some network management software) and in this sense they are commodities.

BUT, as soon as you want to modify, change, upgrade or replace some part of a BMS, you suddenly face the nightmare of proprietary software configuration and incompatibilities.

Energy Managers must break the mouldAnd that's dumb !

Another way in which Building management system companies are completely ignorant of their clients, is that to them one I/O is the same price and value as another. So every sensor is in range or serviceable, reachable or not.  But it really doesnt matter to them that one controls a huge chiller plant, while the other is watching the state of a toilet fan.

So what should you do about it ? - refuse to be a number

Recognising that a building management company (or service provider) is motivated by quantity (of hardware, sensors, network topologies etc) and complexity (the less accessible your system is, the more you are tied into a supplier and over a barrel), you should pull in the other direction, simplify and reduce the scale.

From an energy managers perspective there is a really easy way to do this,..

So which handful of pieces of plant if unserviceable would make your life an utter nightmare ?

Let me have a go (lets assume an HVAC and comfort focus here).

The delivered condition of air is wrong - sensor failure will do that The main boiler targeting mechanism is compensated verses outside air and the outside sensors are shot. The compressor bypass actuator is stuck open - no chilling and the flow header is reading low (so you don't know about it!
grundfos (Photo credit: Johnson Cameraface)

Lo and behold maybe fifteen sensors out of (in bigger buildings) many thousands, and your life is not worth living.  And very easily you could come up with ten scenarios of abject misery.  The key thing is that they time and again involve the same core-functionality of the air treatment plant !  So you do care about 50 sensors or actuators and the building management system companies are interested in selling you another 10 thousand or documenting how each one works, or upgrading the XYZ functionality.

What we try to do is focus on the pain points - and in most buildings there are less than hundred (even very big buildings) - get those right and the rest is detail,  Let them fail and you haemorrhage time, effort and money.  Your controls sytem provider, does not know this about you.  Let him know - channel his efforts focus his mind on what matters to you and your building 

- You may have a client ID - but YOU are not a number 

And knowing that allows you to really show Building Energy Intelligence ! - kWIQly

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Air Conditioning Repair

Air conditioning  ( AC) repair is the most urgent requirement that a typical energy manager faces. This explains why the cost of repair can be staggering.  It maybe that the parts are truly expensive, or that the call out fee is reasonable, but what is pretty much guaranteed is that if you are in need of air conditioning repair, so are many of your neighbours at the same time.

The perfect storm, is the onset of summer, in a poorly ventilated, sun-facing office with inadequate blinds, in a particularly hot and humid city with very poor air quality.

The idea of micro-climates is over-used, but it is clear that if you live in a town where the above conditions all come together in a rush, then the climate of your co-workers will be frosty !  

To save money and energy is not the objective of an energy manager under these situations, he is fire-fighting in an almost literal sense. What this suggests is that a bit of preparedness "out of season", when costs aren't crazy and ice by the tonne is not the order of the day might pay off.

So lets look at a few ideas that will pay off for an energy manager, or more generally what is efficient energy management in this context.

Step One -  first a suggestion, why not bookmark this page right now (so you can come back), and go make a diary schedule for next year say two months before your air conditioning will be a matter of life and death!  Why? - well yes its obvious in part - but here are some other good reasons:
  • Spare parts are available
  • Labor is cheap
  • Demand is low
  • If you need downtime for repair it isn't yet critical
  • Your time will be better spent and stress levels will be lower
If those aren't enough reasons, then maybe we are wasting our time here - I wish you farewell !

If you are still here - great, lets go onto step two...

So what is a good state of repair for an air conditioner?

Note : I am not going to address water borne disease here - Here's a link to the UK health and safety executive on Legionnaires - but it is a nationally specific issue - awareness is a must, and liability is also a motivator - be warned !  

Well it needs to be able to treat air obviously, but what does that imply - obviously this depends on the complexity of the plant?:
  • Filtration - possibly
  • Ventilation (almost always) - fans, motors, drives, frequency inverters
  • Dampers and actuators - often
  • Pumps, variable speed drives, power supplies
  • Drive belts,
  • Compressors
  • Condensate, leaks, valves, drains and blockages
  • And the list goes on - cooling towers, etc etc.
But above all else sensors and controls - absolutely necessary for times and targets!

Why above all else ? - Well if there is no policy on what should be achieved, there can be no energy management, no reasonable filtration of complaints and no strategy.  And without these things your role is meaningless - sorry - but I say it as I see it !

So, step 2 is to decide on a building service standard.

This could reasonably involve occupancy schedules by time-of week, internal space targets in terms of upper and lower limits for temperature, relative humidity and target air quality CO2 concentrations.  But it is also a great time to agree terms with the staff. Do they agree that they can wear lighter clothes in summer (better getting to and from work that way anyway) ?
Will they listen to disciplines regarding keeping windows closed (or open - depending on strategy). Can they organise the workspace more rationally?  Would a small investment in blinds be a good idea? and so on.

Step 3 - Its boring but it is largely true that you can't manage what you can't measure !

So calibration - do sensors that control the strategy represent reality or do you pay for GIGO ! - In my opinion this is the first question to ask an air conditioning repair company - does the machine do what it is intended to do, or "what it wants to do".

Step 4 - Self-help The actual state of maintenance - belts, filters, gaskets, etc do you change them periodically or based on pressure drop (do you have spares ?) - Do you have an easy way of clearing blocked drainage (silly question, but can be a winner )

Sep 5 - Set up emergency support contracts when the demand for business is low, and make sure that there is a strong penalty clause / rebate for non-performance !

Finally - enjoy the summer - when it comes  - and go fill that diary in like I said - AND bookmark the blog :)  !

Boiler energy saving is like running a bar ?

At kWIQly we noticed huge amounts of energy can be saved by controlling boilers or furnaces better. Unfortunately independent reliable advice is hard to find. 

Naturally there are vast numbers of companies trying to sell this or that "solution" , but can they be trusted?  

What I hope to do here is simply to provide a primer or 101 on the subject. If you know what you need - you are more likely to buy it, and not what the salesman is selling. So how do we (you - but let me talk on this occasion as if I'm on your team) save energy?

It's worth looking at this through the eyes of a poor college student (put yourself in his position) who is buying a round of drinks in a crowded bar,  three rules must be observed, not in any particular order.
  • You find out what is wanted - right now (not on the next trip to the bar - not your problem)
  • You try to deliver drinks with least spillage (maximise bang for bucks).
  • You refuse to pay for what the barman spills
Meanwhile the bartender pours what you need (wasting as little as possible) before handing it over. If in some odd world there where more bartenders than were clients and they got ahead of themselves by pouring too many the rest is their problem.

Back in the real world of energy management things are very similar, but there are also some very important differences. Assume we have three boilers (bar-tenders), that you will really deliver heat via pipes (instead of wading through a sea of drunk students) and most of the year you more than enough boiler power (three bar tenders is more than plenty in an empty pub).

The important differences are as follows:
  • Spillage is absolutely unavoidable - the rate of heat lost on the way back from the bar is directly proportional to how full the drinks are ie the thickness of the insulation Maybe we can imagine a little railway track that delivers beers like luggage on a carousel at the airport or dishes in a sushi bar. The hotter the pipe (the fuller the glass)  the more is lost. We could reduce this "transmission loss" through improved insulation, which has very predictable effects (but the benefit is lower the less you are wasting - so it makes sense to evaluate waste before investing).
  • Bar tenders are lazy, boilers are not! A bar tender will only pour a beer when necessary but a boiler lives to work. A boiler can be turned off or turned down, but given the freedom to act within the limits of its' own thermostats a boiler will spend your money just as fast as it can (think of serving water at the bottom of Niagara ) it would spill less if you could turn it down between servings !
  • Boilers are more efficient the harder they work but busy bar tenders make mistakes. So if you are going to let a boiler run, you do want it to run as hard as possible.
  • People know how much they want to drink very accurately (I did not claim this is good for them) - generally it is a simple question of more or not more. Buildings are more choosy -they want a little or a lot or just enough heat to stay comfy.
  • Final difference, heat can be wasted if delivered after people have left the building, but once a bar clears, the drinking stops.  Would you sack a bar tender who left a beer tap running overnight ? - Me too !

So with these differences comes a set of problems, which is not as instinctive as buying a round of drinks.  However, (and perhaps surprisingly) the optimum strategy is not all that difficult to figure out.  Lets go ...

We need to apply a simple set of rules about when to work and when not !
  1. Always deliver heat at as low a temperature as you can, to get the job done (carry half empty beer glasses to avoid spillage unless a full glass is ordered).
  2. Use the least number of boilers possible to get the job done (bar tenders are more clumsy when overworked) - boilers are more efficient when working really hard.
  3. Do not let a boiler "idle" or "tick-over", if it is OK to switch it off -  do so  ! (the hard work reason).
  4. Rooms don't know how much heat they need or when they need it - like drunks.  Watch what is needed, when it is needed and deliver as rarely as possible (off at night)
There is some devil in the detail - lets get our mops out and see if we can sort out that spillage !

How fast should you pump the water round the system ?

Boilers get hot and give off heat - also heat goes straight up the flue (chimney) if it can. Ideally when a boiler is burning gas, you want to carry away as much heat as possible, otherwise it gets lost (rather like a barmen stacking hundreds of beers on a bar that nobody is delivering).  The implication is that heat should be carried away fast.  Each boiler has a "rated flow rate", if you burn fuel without making sure water is pumped fast enough, you are pushing energy up the flue.

You can save electricity by using a variable speed pump  ( a VSD drive or frequency inverter matches the AC supply to a lower rotation speed ) BUT, if water is flowing through the boilers slowly you can lose much much more (a pump may use a few kilowatts to satisfy a boiler that delivers megawatts.

The heat should be circulated around the building fast as well, if it is delivered slow, it must be delivered hot (more losses at boiler and along the journey = full glasses).

If the point of delivery throttles flow when satisfied (the drinkers ease up on their pace is analogous to air conditioning unit cooling or heating valves closing), then there is an opportunity to deliver less - so reduce the boiler heat (deliver emptier glasses) to keep the rate of pumped delivery high - a VSD drive can be an excellent tool in the armoury for this

How many boilers ?

Too many bar-keeps is a really bad idea (hot metal)  suppose you need to deliver a number kW load and you have two boilers that can deliver 650 kW and one that can deliver  400 kW ( use 1000BTU instead of kW if you prefer - the analogy holds) - Its all about how hard you want to push

This means
0 - keep all boiler off 
1-400 use the 400 kW boiler
400 - 650  use the 650 kW boiler
650 - 1050  use the 400 kW boiler and the first 650 kW boiler
1050 - 1300 use the two 650 kW boilers
and above this use all three boilers.

This is called demand sequencing and from three boilers you can have six steps. For historical reasons (a reversible camshaft) there are traditionally only two sequences of 4 possible steps implemented summer-winter-winter and winter-winter-summer (where the bigger boilers are called the winter boilers) - This is very weak thinking.  What is notable in the "correct" solution is that the smallest boiler goes on and off at each load step change.  This is very important because a "blown" or "charged" boiler wastes a lot of energy switching on or off (the combustion chamber is purged with cold air before and after burning to reduce explosion danger -by clearing out un burnt gasses.

Demand management - How do you know how much to pour ?

Sorry - this is too big a topic- the subject of a later post, but as a starter, given that buildings are built to keep heat out, and that we sleep at night it should be no surprise that weather and time of day are the two biggest single factors in deciding.

Hope you enjoyed the post - follow @kWIQly to be advised of the future instalments

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When you must manage what you didn't measure

Every so often if you work in energy management you hear that defeatist whine - you can't manage what you can't measure.

Sure I get it, measuring things is good ! However, sometimes a manager has to deal with missing information.  In this post I am going to look at a very common problem with energy management - the missing meter reading.  Look it happens, so let's get used to it already!

The classic report of a string of meter readings is shown showing cumulative true readings
 reported in light blue and then in purple reported values.  During our example, twice the reading technology fails. At the end of the missing period a sudden spike of apparent consumption occurs as our reported reading suddenly catches up with our true reading.

The question I am asking is what are we to do with the data?

missing energy management data
This happens all the time, and I see three responses by the "Smart-meter" reading community, all of which are wrong for energy management purposes and all for possibly well-meaning reasons.

  • Bury head in sand - This is the easy and most common path.  The automatic reading company (for that is all they are "smart" is a misnomer) says, aha, but you must have data that corresponds to fiscal metering (the money), otherwise it will cause confusion - so we report what we know !
  • Linear interpolation - You can't manage what you cant measure (there it is) so lets just join the dots that represent what we do know with a straight line. Essentially this assumes a period of constant average consumption.
  • The "Smart fix" - Looking at the lines above, we can see a pattern of consumption, when we do get readings, so we can fill in the patterns on the basis of the information that we do have
The correct action, naturally is to remember the source data (the reconciliation is necessary), and delete all the unknown data ! - If we do not know a pattern, to assume it is to suggest that metering at this resolution is unnecessary, because we know what is happening anyway.

This is the difference between financial and management accounting, and an energy manager accounts for energy - but must also manage it, If he needs reconciliation, he needs it at billing intervals (not at half-hourly intervals) so yes the big picture is to take the diffenece between two known readings as sacred.  However, if we care about knowledge regarding distribution of load, we are working with statistics.  A missing data item is not a problem (and it is far better than an observation that re-inforces a pattern that may be wrong - to do so adds no value (and can confuse) - The temptaton to make data pretty must be avoided.  Report and work with what you know - do not give yourself the artifical comfort of looking at fraudulently complete data, and thereby innure yourself to the truth. Best solution, use the evidence to make your meter data provider work harder and then get on with the job - Managing with the measurements you have, not excusing yourself on the basis of those you don't have !

Smartmeter beyond pretty graphs to energy management

Beyond pretty graphs and toward energy management.

The world knows Smart-Meters are coming and numerous companies support acquisition and display of energy data, but data out-of-context means nothing to an energy manager.

Here is an example of consumption over time 

– can you read it and see when energy is wasted ?

- No ,   neither can a typical householder !

So the conditions of things in a building (temperatures, valve positions and so on) can be shown, but the meaning or relevance of the data is not drawn out or obviously expressed.

Looking at the above heating data, it really isn't obvious when waste happens, but fully automated examination can highlight waste, and save energy managers time and effort  :

This video simply demonstrates how in a few seconds and energy manager can provide strong evidence that heating can be switched off in a particular building at a certain outside temperature .

Certainly the reports made available need to be tailored to the level of understanding of a particular user, and given that we have many such diagnostics available; that can be fully automated (we can provide independent reliable weather data) they can extract opportunity from portfolios of buildings and highlight savings opportunity in the form of prioritised reports.

Seeing opportunity allows an energy manager (or householder) to take corrective action with appropriate support – but our industry is providing neither investigation nor support!

This makes our point - “ data out of context means nothing to an energy manager “, but we believe that use of the information (rather than mere data provision), can benefit all parties.

Corrective action depends on client circumstance; for a householder - a call to their gas company, a hotel chain might commission an expert to advise, and a far bigger concern might pass an investigation ticket down the line to their facility managers (backed by supporting evidence).

None of these actions take place with the problem undiscovered, so opportunities are “going begging” for want of a solution provider. Of greater interest is that once corrective action has been taken, from subsequent data proof-of-savings can be delivered, again automatically. Hand-in-hand with 'proof of savings' comes personal success for energy managers, lower “churn rates” for service partners and environmental benefits for all, including corporate responsibility “good-news” as a “nice-to-have”.

We have the tools to identify these and many other problems automatically through pattern recognition, before an energy manager raises a finger. We are interested in providing this functionality embedded in the web-portals of companies proving Smart-Data access.

Balance Point Temperature - tough maths made easy

Identifying the balance temperature of your building is the first step to classical energy management.

This post does three things:
  • It looks at a far easier way to get the job done
  • Explains why it is so important,
  • Details how some newer diagnostic technologies can really enhance the understanding of heating and cooling in buildings
here we go...

So, a far easier way to get the job done

Here is a very quick video showing kWIQly automating the mathematics for a client building. All kWIQly needs is a history of energy consumption associated with heating or cooling, and to know where your building is.

Given Latitude and Longitude or an address kWIQly grabs the weather data - saving you the trouble.

There is a thorough description of the process done the "hard way" at Berkley Uni.

but then ... Why would you ?

Why is it so important - the easiest way to understand the concept is by interpreting the graphics.

Here is a fixed-screen shot for reference: 

The balance temperature or balance point temperature is (for heating) the outside temperature when you are just on the border of needing heating or not. (11.5 Celsius above).  Above this is summer base load - and below weather response (or did you watch the video !)

Different buildings are different sizes, have different insulation, glazed areas, typical weather exposure, shade and etc, plus they have different accidental ( organic heat gains ), coming from Pcs, lights , people, cooking and so on.

But this single temperature takes all of that into account. 

On one side of it all heating effort is waste (or contributes to greater cooling costs!) including pumps to circulate heat, boilers on low load and so on.  

On the other side bare minimum heat should be available (as cold as compensation of zones allows) and for a absolute minimum period of the day.  Why the bare minimum ? - because plant is often very inefficient on very low load.

That will be enough to heat the "chillier corners" of the building.  As temperatures fall, a liner response pattern develops, and it should remain linear all the way to the coldest outside temperatures that the building experiences.

Newer diagnostic technologies

Update February 2012 : You can now get degree-days for anywhere on the planet calculated for free by kWIQly

In reality, the balance point temperature is not fixed.  It is dynamic for three reasons:

  1. It moves lower if a building is unoccupied and internal temperatures are allowed to fall (because heat loss is slower),
  2. it falls if the ventilation rate falls, and curtains are drawn(no need to heat all that cold outside air before you put it into the building and better insulation),
  3. but it rises as internal activities fall.

So depending on the nature of the building and its occupancy patterns, the temperature at which you should make sure no heating can happens moves - getting it wrong is wasteful - always !.  

Control systems can easily be set up to maximise the benefits from this phenomenon, but first you need to do the maths!

Happily with smart meter data available, we can automate all of that, so 
a) send us your data, or better
 b) have a word with your smart-metering company or utility and have them get it to us.

 The rest is a piece of

Energy Savings - They think you ought to know

I was editing a video of our new energy analysis tool last Sunday, when the son of my neighbour (an engineering student) asked me, "Does it make any sense that if you lower your thermostat at home by one degree that whoever you are you will save 5% of your heating energy"? 

Now he is a smart young man - so we started discussing it...

We first compared their house with mine – mine is bigger but older (1684 – the oldest chalet in the village and the wiring standards are pre-Faraday also ! ), both are wood frame – his far better insulated but his parents prefer much higher indoor temperatures. 

Their heating system is modern, though both of us heat with local wood, I use a traditional wood-fired oven. His parents use more consumer electronics. So, pretty much the only things these buildings have in common is the local weather (Swiss Alps), the Laws of Physics – and the fascination the owners have in sustainable living !

If we were to rely on the disinformation and nonsense on the subject published by authorities and people who should know better, we would very rapidly have reached the wrong answer.

I searched “turn thermostat degree save” at "scroogle" (scroogle allows me to use the familiar Google tool but eliminates bias in results due to their recording my location and normal search interests etc).

The results (tabulated below) suggest that most “authorities” put savings at 1% - 6% per continual degree (Fahrenheit) of heating turn-down, with the average at around 3%. So thats a specific impact. If my mortgage broker said I could save 3% on repayments I would be excited – but if the quotation was 3% plus or minus 3% I would be far less, motivated. When the savings are quoted as 1% savings per eight degree-hours as six out of twenty opinions suggested, as a consumer I would be completely confused. There is archaic Anglo-Saxon phrase for communication standards of this ilk, to wit : “complete”.

Some authorities advise that climate, construction and preferences have an impact, but this is not reflected in their “facts”. For example there is no obvious geographic or weather pattern (extremes were reported in Great Britain, California & New Mexico and more modest figures in Wisconsin, Washington DC, Louisiana and Kentucky).

So lets have a think about this...

Surely we must think in terms of a particular local climate. Now we have local weather data for anywhere on the planet – so getting a local set of degree-day data is easy.

Energy Management Screen shot

First you need to select a balance temperature - the temperature when no heating is required . To do this you can just map consumption against weather. And to do that we need to upload consumption data. Maybe we have it written down or in a spreadsheet, or better yet we can download it from a Smart-Metering provider or maybe a utility company. So we can upload it somehow … If we are lucky we have a good three years of data – but anything is better than nothing !  (OK I am cheating this is gas data from a client - I count cords of wood burnt )

Graph of Energy Consumption vs Weather

Given weather and consumption we could find the balance temperature of the two buildings. Here is theirs:

Automation of Balance Temperature Calculation

Thats fairly clear isn't it! Above 11.5 Celsius – no heat is required – in summer use is for hot-water cooking etc. So balance temperature is 11.5 Celsius. A useful figure to know if you are controlling a building...

(By the way four years ago it was proven conclusively by an “authority” that it was impossible to automatically calculate balance temperatures – “Whooops!”)

So now we can draw a Degree-Day diagram - lets assume fuel has been logged in “logs”. (Logging is actually throwing a log on a rope over the front of a boat and writing down how long it takes to sail past – logging boat lengths for navigation – Think Columbus)

Chart Show Degree-Day consumption volatility

So on a very cold day we burn 14 logs – but in summer only 2. Each day represents a weather load and a number of logs.  For fun we also coloured the over-normal spends red (because we can) - this represents an "inconsistency cost"

In an office the scatter is important by day of week because occupancy patterns change (or should)

Mission nearly accomplished ...

So to calculate how much we save by dropping the internal temperature by one degree, all we need to do is move each dot down and to the left by one degree-day representing a reduction in load (parallel to the best-fit line, but not allowing the consumption to intersect the bottom or left axis - negative consumption disallowed).

For this building one degree is worth about 10% - Celsius so some of them are right !!!

Hmmm – a new feature for version two (planned January 2012 release) – So we can calculate how much you would save in your house or other building, based on your weather, your energy use patterns and on your building – then you could rely on facts rather than letting some “authority” on energy have a guess !

If you like the idea, do watch the screencast at for a bit more information – its illustrative and three minutes only so is by no means complete.

And, even if you think what we are saying and doing sucks – please do tell us – we need your feedback

Finally if you are an authority on energy, a utility company, or a smart meter operater, or even if you have your own reliable energy records, do get in touch.

Maybe we can figure out something – Just like my young neighbour Ueli and I did on Sunday afternoon. And if we can figure stuff out for people, something that they can use to really save energy based on their buildings, based on data from their buildings – rather than some irrelevant benchmark – wouldn't that be cool – or maybe hot - to a degree !

Oh - and here are those authorities on the subject I promised

Ref (links below)
% Saved for
1 Fahrenheit change
Each 1-degree drop for an eight-hour period reduces your fuel bill about one percent.
For each 1 degree you turn down the thermostat in the winter, you’ll save up to 5% on your heating costs.
Save: 1 - 3 percent per degree, for each degree the thermostat is set above 72 degrees
For every degree you lower your heat in the 60-degree to 70-degree range, you'll save up to 5 percent on heating costs.
The rule of thumb is that you can save about 3% on your heating bill for every degree that you set back your thermostat” full time, says Bill Prindle, deputy director for the nonprofit American Council for an Energy-Efficient Economy.
One rule of thumb is that each degree Fahrenheit you set the thermostat back over an eight-hour period translates to a 1 percent savings in heating costs.

No value given

In fact, you will save an average of 3% on your monthly bill for every degree you turn your thermostat down
Kentucky, Louisiana
 In general, adjusting the thermostat by just a single degree in the summer can either cut or increase cooling energy use by about 4-8%.
Typical savings are about one-percent per degree set-back for each eight-hour period.

Yet, for every degree you lower the thermostat, you'll save between 1% and 3% of your heating bill.
1% - 3%

For every degree you raise your thermostat above 80 you will save approximately 2 - 3 percent on the cooling portion of your bill.

In heating mode, reducing your thermostat setting
by 1 degree Fahrenheit for eight hours will save about
1 percent on your heating bill. In cooling mode, e ach
degree you set your thermostat above 75 degrees
Fahrenheit cuts your cooling costs by about 3 percent.
HVAC experts estimate that for every degree the thermostat is dialed down, you can save 1-3 percent on your heating or cooling utility bill. 
You can save 3 percent on your heating costs for every degree you reduce the temperature below 70 degrees F. for the entire heating season. 
Washington, D.C.,
By turning your thermostat back 10°–15° for 8 hours, you can save about 5%–15% a year on your heating bill—a savings of as much as 1% for each degree if the setback period is eight hours long. The percentage of savings from setback is greater for buildings in milder climates than for those in more severe climates.

A savings of 3% to 5% can be realized each month for every degree the room thermostat is lowered.
3% - 5%
New Mexico
For every degree you turn it down, you can save about 10% of your heating bill  (Celsius)
Your heating costs will go up by 8% each time you increase the temperature by just one degree. (Celsius)
Carbon Trust
No value given

Twenty results

    "21 Aug 1999 ... Gradually, you might be able to go down 3 or even 4 degrees comfortably and save a chunk of money. 4. Try turning down the thermostat 5 to ..."
    "Reduce the setting to 55 degrees at the end of the day. (For each 1 degree you turn down the thermostat in the winter, you'll save up to 5% on your heating costs ..."
    "(Save: 1 - 3 percent per degree, for each degree the thermostat is set above 72 ... your dishwasher only when it is fully loaded, and turn off the dry cycle and air ..."
    "Turn down your thermostat to 68 degrees. For every degree you lower your heat in the 60-degree to 70-degree range, you'll save up to 5 percent on heating ..."
    "2 Nov 2008 ... We already keep the thermostat at 63 degrees…no exceptions. And socks, sweaters and blankets are ready to go. I will not be turning the heat ..."
    "3 Dec 2010 ... Does turning down the thermostat at night save energy? ... to bed, turning the thermostat down from 68 degrees Fahrenheit to 60, then turning it ..."
    "You can also make savings by using your controls more effectively: Turn down your room thermostat by one degreesave around £55 and 230kg carbon dioxide ..."
    "14 Sep 2011 ... There are literally dozens of things you can do to cut back on your heating (and cooling) costs in your Jeffersonville home."
    "If you choose to turn up your thermostat by four degrees in the summer, you'll be saving something close to 16-32% in energy costs. You'll also be avoiding the ..."
    "In time, you might be able to go down three or four degrees comfortably and save money. • Try turning down the thermostat five to ten degrees at night, and then ..."
    "Save money on your utility bills, and reduce your carbon footprint, by turning down ... Yet, for every degree you lower the thermostat, you'll save between 1% and ..."
    "Can I turn my air conditioner off when I leave or should I leave my air conditioner on during ... For every degree you raise your thermostat above 80 you will save ..."
    "Will a programmable thermostat really save ... by 1 degree Fahrenheit for eight hours will save about ... If I turn the thermostat way up, my home will warm up ..."
    "Every 10 degrees you dial down the thermostat can knock 3 to 5 percent off your ... In other words, the amount of energy saved by turning down the thermostat ..."
    "Turn them off when their job is complete. 3. Set your thermostat at 68 degrees F. during the day and 60 degrees F. at night. You can save 3 percent on your ..."
    "9 Feb 2011 ... By turning your thermostat back 10°–15° for 8 hours, you can save ... on your heating bill—a savings of as much as 1% for each degree if the ..."
    "Turning down the heating element thermostat(s) by 10 degrees can save you as much as $10 monthly. Repairing hot water leaks can save 10's of dollars ..."
    "30 Apr 2008 ... Thermostats (usually a dial on the wall) set a maximum temperature for ... For every degree you turn it down, you can save about 10% of your ..."
    "Energy saving heating tips to increase the energy efficiency of your workplace and lower your ... Don't turn up the heating unless you really need to. Unless it's just too cold for comfort, try to keep your thermostat at 19°C. Your heating costs will go up by 8% each time you increase the temperature by just one degree. ..."
    "Some thermostats are equipped with schedules in which you can set differing ... In the winter months, do you turn (or does your thermostat turn) your heat down to save. ... Turn your sleeping areas down to about 17-18 degrees celcius (likely ..."