RefurbN16

Tag: Renting

  • Energy Efficient Lighting Pt 2 – Halogens

    The first post on lighting took a look at CFLs, the cheap and effective replacement for standard incandescent lamps*, but over the last couple of decades, many homeowners have opted for halogen lighting.

    Halogen lamps are incandescent i.e. electricity passes through a tungsten filament which heats up and emits light. They differ from the standard incandescent bulbs in that the filament is encased in a capsule full of halogen gas which reacts with the filament in a process called the halogen cycle.

    Halogen lamps have a higher efficacy than standard incandescent lamps, but you generally need quite a lot of halogens to light a room so you usually end up using a fair bit more electricity for the same effect. Now, with electricity prices high and rising, what can be done to reduce the electricity consumption from all those halogens?

    The cheapest option to cut electricity consumption from halogen lighting is to buy a batch of energy saving halogen lamps. These cost a bit more than the normal ones but use about 30% less electricity and they usually last a bit longer too.

    You can also buy halogen replacement CFLs. These are little compact fluorescent lamps that are folded up into a halogen-sized fitting. They’re not cheap (anywhere between £10 and £20 each for a good quality lamp) but they are a lot more efficient than the energy saving halogens and should last a lot longer.

    If you have your halogen lights on a dimmer system, be careful as CFLs often can’t handle this, and as with all CFLs you want to make sure that you get one with the kind of light output that you feel comfortable with. Check this post to see what to look for.

    Finally there is also the LED (light emitting diode) option.  LED lighting is much more efficient than incandescent lighting and LED lamps have much longer lifetimes (at least the quoted lifetimes are much longer, actual lifetimes remain to be seen).

    The main barrier to the widespread uptake of LED lighting now is cost. Good quality LED fittings are still eye wateringly expensive (around £20 to £40 each) but as they’re so efficient and as they should last tens of thousands of hours, they do pay for themselves many times over in energy savings and replacement costs over their lifetime.

    I’ll go into more detail on LED lamps in a future post, but briefly, the technology has moved on a lot in the last few years and you can now buy really good quality lamps.

    Prices will come down in the next few years so it might be worth holding off for a little while, but if you are going to be redoing the interior of your house and you currently have halogens, it’s probably a good time to consider this technology.

    Useful tip: if you are considering investing in these more expensive halogen replacement options, then the best tactic is to replace the bulbs that have the highest use first. By replacing these bulbs you will see the biggest drop in your electricity consumption and they will pay for themselves in the shortest time.

    * A lamp is what is more commonly referred to by people outside the industry as a bulb. What we normally call a lamp would be called a luminaire in the industry.

  • Energy Efficient Lighting Pt 1 – CFLs

    The widespread roll out of compact fluorescent lamps (CFLs) has caused quite a stir to say the least – these innocuous little things have upset quite a lot of people, with some feeling the need to take drastic action.

    Certain sections of the press definitely haven’t helped, spreading some pretty extraordinary stories about CFLs over the last few years; stories which have been designed to spread confusion and fear of what is a very good and safe energy efficiency technology.

    People have been working under fluorescent lighting for decades and a CFL is not very different to an office fluorescent tube – it’s just been folded up on itself into a much smaller space.

    That’s not to say that they’re without fault. They contain a very small but significant amount of mercury and therefore need to be handled appropriately (more on that in a future post), in some cases they can take a moment to warm up which is not what we’re used to after a century of incandescent lighting and the light that some give out is not the best.

    Another problem is that a lot of unsolicited bulbs of varying quality have been distributed under the Carbon Emissions Reduction Target, with people receiving bulbs through the post with the wrong fitting, bulbs that give out a harsh light and bulbs that looked, well… pretty damned ugly.

    But it definitely doesn’t have to be like this so this post is dedicated to the things to look out for when hunting for the perfect CFL.

    CFLs use about a quarter of the electricity of a conventional incandescent. This is a big saving and one that means that you shouldn’t wait until an incandescent bulb blows before replacing it.

    The embodied energy of a CFL (the energy used to produce it) is greater than the embodied energy of an incandescent bulb, but the efficiency savings you get from using CFLs greatly outweighs this additional energy so swap all your remaining incandescent bulbs today.

    Defra has published a comprehensive life cycle assessment of ultra efficient lamps which is worth reading if you want to know more about the environmental impacts of different lighting technologies.

    You can pick up very cheap (often subsidised) CFLs all over the place nowadays but I find it’s worth spending a few pounds on really good quality bulbs. On average a CFL will save a few pounds each per year and if it’s replacing a high use bulb it’ll save you a good deal more than that and over the lifetime of the bulb they will save you anywhere between £50 and £100 per lamp.

    In different situations you might be looking for different qualities in your CFL. For example on an upstairs landing you might want one that warms up quickly, in the living room you might want a warmer light while in the kitchen you might want a bluer and brighter light.  As these types of bulbs last for a good 10,000 hours, it’s worth finding the right one for your needs.

    The thing that many people seem to object to most is the colour of light that CFLs give out, known as the Colour Temperature.

    You can buy fluorescent lamps in a range of colour temperatures from 4000K (or 4000 Kelvin, sometimes known as “cool white”) which gives a stark, blue light, to 2700K (sometimes known as “warm white”) which gives a much warmer colour very similar to incandescent bulbs. Natural daylight is very blue and has a colour temperature of about 6500K.

    For most people this lower colour temperature (which confusingly gives a “warmer” colour) is what they should be seeking out.

    Another measure of the quality of light which a bulb gives out is the Colour Rendering Index. This measures how faithfully the colour of  a surface appears under different light sources compared with an ideal light source.

    The scale measures up to 100 and the higher the CRI the better. You can buy CFLs with a CRI of over 80.

    Efficacy is a measure of how efficiently it converts electricity into light and is measured in Lumens per Watt (Lm/W). You will sometimes see CFLs with the same power consumption but different Lumen output (i.e. one is brighter) and this is an example where one lamp has a higher efficacy than the other.

    The use of Watts to describe a bulb’s brightness is being phased out at the moment and you’re going to be reading a lot more about Lumens in the future (both will be displayed on packaging). It makes a lot more sense to use Lumens as this is a measure of brightness whereas Watts are a measure of power consumption.

    The following table gives the brightness that incandescent lamps of different power give so you can work out what brightness a replacement CFL should be.

    The “clear” column gives the brightness of incandescent bulbs made with clear glass and the “soft” column is the brightness for the frosted sort of bulb:

    Power (W) “Soft” Brightness (Lm) Clear Brightness (Lm)
    40 335 365
    60 575 620
    80 830 895
    100 1075 1175

    (Source: EST Lighting Specification)

    In common with all lights, including incandescent bulbs, CFLs lose some brightness over their lifetime, but if you buy a good quality bulb they will give a good light output for a very long time.

    A bulb’s start up time is also important for many people. CFLs switch on very quickly (less than a second) but then take a while to run up to full brightness. They can take up to a minute or so to reach their maximum brightness, but what is most important is how quickly they get up to a reasonable brightness.

    If start up time is important to you then look for “fast start” bulbs that warm up quicker than regular bulbs. In some cases I find it’s nice to have a slow warm up time, especially in bedside lights so that you’re not blinded in the middle of the night.

    So that introduces the technical aspects to look for. Size and shape should also be considered as some CFLs won’t fit as neatly in a lampshade as others but there is now such a huge range out there that you can find excellent bulbs for nearly every situation and the number of good quality bulbs is growing all the time.

    For the record, my favourite CFLs are made by Megaman but there are a load of good ones out there. At some point I might do a post collecting together the best bulbs from each manufacturer. Feel free to post your favourites in the comments below.

    In future posts we’ll look at other aspects of lighting such as halogens, what to do if you have dimmer switches and other technologies such as LEDs.

    Power (W) “Soft” Equivalent Clear Equivalent
    40 335 365
    60 575 620
    80 830 895
    100 1075 1175

  • Curtains and Radiators

    This topic came up tonight: what do you do with a curtain hanging over a radiator? And why are radiators sited under windows anyway?

    Back in the day, radiators were located under windows for a counterintuitive, but valid reason, although it has more to do with comfort than energy efficiency.

    Imagine a room with single glazing and a radiator on the opposite wall. The air beside the window will be cooled and will sink as it becomes denser. At the opposite end of the room the air is warmed by the radiator and will therefore rise.

    These two effects combine to circulate the air around the room, but this circulation will draw cold air from the window down into the centre of the room where you are sitting.

    Stick the radiator under the window and it will warm the air beside the window, causing it to rise into the room. At the other end of the room it will descend, but it should be at a warmer, more comfortable temperature. It’s worth noting that with double glazing, this isn’t really a problem and you can locate your radiator wherever is most convenient.

    So radiators are usually found under windows which have curtains which, more often than not, hang down below the top of the radiator.

    Having them hang in front of the radiator is a big no no. All that lovely heat will rise up behind the curtain, right against the single glazing and will be trapped there before leaking out to warm the outside air.

    Tucking them behind the radiator can also be counterproductive. Radiators work best when they have a free and unobstructed flow of air around them, helping to set up the convection* currents that circulate warm air around the room. For this reason you definitely want to avoid radiator shelves and radiator cabinets.

    If you take a look at a typical radiator, you’ll see there are the thick bits through which the hot water flows, and thinner fins that transfer the heat to the air. It’s these fins that you need to keep clear and unobstructed, and tucking a curtain around them will reduce their effectiveness.

    So what’s the solution? Cut the curtains so that they hang a bit above the radiator and then find some way of holding them flush against the wall. Hooks? Velcro? Elastic? Whatever works best. Just make sure that as little hot air as possible escapes behind the curtain and as much air as possible can flow around the radiators.

    By holding the curtain flush against the wall, you will not only prevent warm air from rising behind the curtain, but you’ll also trap a layer of air there. Air is a fantastic insulator, as long as it is kept still, so if you can keep the air between the curtain and window  as motionless as possible, you’re on to a winner.

    * radiators are really badly named – they’re convectors, not radiators; but radiators they shall be known as for ever and ever…

  • Fridge Freezer Temperature

    I picked up a bunch of thermometers this week for TTSN people to check their freezer and fridge temperature. These thermometers are cheap as chips (and apparently reasonably accurate – thanks WRAP) and could save you a tidy little sum if you’ve been overchilling your food. I’ve just popped one in the freezer compartment and it seems to be reading -19 degrees. According to Iceland (and they should know)…

    Star rating Location Temperature Storage
    * Ice box -6 degrees 1 week
    ** Ice box -12 degrees 1 month
    *** Ice box -18 degrees 3 months
    **** Freezer -18 degrees Long term

    So apparently I can store frozen food long term but I don’t really need the freezer compartment as I buy all my food fresh, in small quantities, and eat it straight away. But I can’t turn the freezer part off and leave the fridge part on.

    So what about switching the whole thing off? In winter I could get a cool box and stick it in a shady spot out on the balcony – you don’t want your food (or indeed beer) to be frozen and thawed as would have happened quite a lot this year so a cool box should provide a bit of a buffer.  In summer I think I’d need to switch it back on, but if I could switch it off for half the year…? It seems some are already trying it.

    Of course you don’t want to save CO2 by cutting your fridge or freezer consumption if your food is going to spoil and be wasted.

    I’ve stuck my fridge freezer on a plug in electricity meter to see what it consumes over 24 hours on its current setting. I’ll then increase the temperature and see what the difference is – empirical science going on right here, just for you lucky people!

    1st Results – OK over the last 24 hours my fridge got through 0.4kWh, very roughly suggesting consumption of 145kWh and 80kgCO2 per year. But I checked the temperature in the freezer compartment at one point and it was down to -14. This was towards the end of its off cycle and I’m guessing the -19 reading was taken somewhere around the end of the on cycle. I’ve cranked the thermostat from “3” to “4” and we’ll see what happens (I’m not even sure if it’ll make it colder or warmer at this point).

    2nd Results –  Consumption over 24 hours at the “4” setting was 0.54kWh, a 35% increase. Next I switched it up to “5” and consumption increased to 0.71kWh, a 30% increase again. I’ve now turned it down to “2” and we’ll see how it goes.

  • Landlord’s Energy Saving Allowance

    For those of us who rent there are much fewer options open to us when it comes to reducing our CO2 emissions in the home. The no cost and low cost measures are well within our grasp and they can make significant savings, but to make bigger cuts money needs to be invested.

    As a renter, there is little incentive to invest in energy efficiency measures as you may only be living there for another year or two, and your landlord may not be interested in improving the energy efficiency of the homes they own because they don’t pay the bills.

    To help break this Catch 22, there is a nice little incentive to tempt your landlord into making that investment: the Landlord’s Energy Saving Allowance (LESA).

    This is a tax deduction which allows a landlord to reduce their taxable income by the cost of certain energy efficiency measures up to a value of £1,500 per house per year.

    The measures covered by the LESA are:

    • Cavity wall insulation
    • Loft insulation
    • Solid wall insulation
    • Draught proofing
    • Hot water cylinder insulation
    • Floor insulation

    Other measures such as double glazing and boiler replacement may be entited to other tax deductions.

    If your landlord fits loft insulation, floor insulation and draught proofing in your home and it costs, say £1,000 in total, they can deduct £1,000 from their taxable income at the end of the tax year.  If they pay tax at 40%, the insulation will end up costing them £600 rather than £400, if they pay tax at 20%, the insulation will end up costing them £800.

    The LESA is open to both individual and corporate landlords (although it cannot be claimed if the let is under the Rent A Room Scheme or a holiday let) and will run until 1st April 2015.

    As energy prices continue to rise, renters will become increasingly interested in the energy efficiency of prospsective homes. Landlords now have to show an Energy Performance Certificate to potential new renters and by taking steps to fit insulation and other energy efficiency measures, the rating will improve making the home more attractive.

    The LESA coupled with the fact that a wide range of energy efficiency and microgeneration measures qualify for a reduced VAT rate of 5%, makes a strong financial incentive for landlords to improve the energy performance of the homes that they own. So get friendly with your landlord and try and persuade them to takes steps to improve your home.

    For more information see the DirectGov page.

  • DIY Chimney Balloons?

    Do you have an open fireplace in your home? Go over to it and see if you can feel a draught going up the chimney.

    If the fire is not in use then a really smart move is to block up the flue. If your fire is in occasional use then please, please, please be careful if you do stick something up there – some sort of reminder in eyeshot might be a good idea.

    During the summer months, make sure you remove the obstruction to let any moisture that might have built up clear away.

    I’ve been investigating chimney balloons but all I can find are ones priced somewhere north of £15 which to my mind is just a tad expensive. So I’m opening it up to see who can come up with the best,  cheapest, most sustainable DIY solution.

    Someone suggested using the foil balloon in a box of wine. Would that work? I think it might on narrower chimneys. Thoughts?