GREENer HOUSE

The scene above, which I photographed in my kitchen this week, is the beginning of a revolution in the way I light my house. My entire kitchen is now illuminated with LEDs, using less than 30 watts to light the entire, 5m x 5m space.

Two turning points set me in this direction. The first was a leaky roof, which blew out the transformers on one of the low-voltage halogen fixtures mounted to the ceiling. This gave me a good opportunity to start from scratch with a 220v, GU10 fixture, since LEDs, unlike halogens lamps, are better suited to ordinary, mains voltages. (Remember: Low voltage does not equal low wattage.) At Lighting Warehouse, I found a three-bulb ceiling light with a design perfectly suited to LED globes, since the radiating fins that cool the bulb are exposed to the air, as you can see above. I paid R360 each for two of these fixtures.

The second turning point was the downward slide in LED prices. I thought I had found a good deal in May, when some Makro stores were offering both Philips and Osram LED downlighter globes to replace 35 watt halogens for R295. Then I found the Osram LED at Lighting Warehouse for R250. Now that same bulb at Lighting Warehouse has dropped to just R200!

If R200 doesn’t sound to you like a bargain price for a light bulb, let me take you through the math. The Osram Parathom PAR16 35 bulbs you see pictured above use 5 watts to produce the light of an ordinary 35 watt halogen. (Actually, my Watts Up meter says they use just 4.8 watts.) If the light is on 5 hours a day at R1 a kilowatt hour—we’ll all be paying more than that by next year—it will save R55 every year on electricity alone. But the savings are greater than that because LEDs last just about forever. Philips puts a 3 year warranty on its LEDs and Osram offers a 5 year warranty. But the bulbs are rated to last many years longer. Over the course of two years, you would expect to replace a R40 halogen once, and the cost of two halogen bulbs plus the excess electricity they use is R190, about equal to the price of the LED. After two years, the LED actually pays dividends.

I chose the kitchen in part because it’s the most-used room in the house. But at R200 for LEDs, I will also consider replacing halogens in rooms that are used less constantly. The R200 Osram LED is not meant for dimmer switches, so for now I will avoid rooms with dimmers. The Philips Master LED bulb at Makro is dimmable, but I have not seen it for less than R295. By my calculations, even if the lights are on just 3 hours a day, the R200 LEDs will pay for themselves in three and a half years. (These simple calculations do not take into account the time value of money, the interest you could have earned if you had saved your R200 instead of investing it in green technology. As I’ve said before, you wouldn’t charge Mother Earth interest, would you?)

The quality of the LED lighting in my kitchen should give no one pause. LEDs have a reputation for projecting a very narrow beam. That is somewhat true for these Osram bulbs, but since they were replacing halogen bulbs that already had beams of 36 or 38 degrees, these 35 degree lights do not have a noticeably greater spotlight effect. I do think that eight bulbs would illuminate the corners of the kitchen a little better than six, but I felt that way about the halogens as well. My Osram LEDs are listed as “warm white,” and their colour is good, just slightly cooler than a halogen, but still warm. Most LEDs have a Colour Rendering Index of about 80 out of 100, which is considered very good, but not perfect. I would not choose them for an artist’s studio, but I don’t think anyone would notice the difference even as they walk between my halogen-lit entrance hall and into the light of the kitchen LEDs.

I have not yet seen LED replacements for 50 watt halogens in the stores; they will be here soon. One day we will have affordable, ultra-efficient LED bulbs to suit every fixture. But my kitchen is proof that there is no reason to wait for that day to get a head-start on a greener future.

Not such a bright idea

What grown man would get excited to see a light bulb selling for less than R100? Me, if the lamp in question uses ultra-efficient light emitting diodes. LEDs are the future of lighting, with low power consumption and incredibly long lifetimes, but their high prices have kept consumers away.  So when I noticed a R94 rand Eurolux LED at my local Builders Express, I took a closer look and took notes. The last LED globe I had seen that was meant to replace a halogen downlight had a R372 price tag on it. Was this too good to be true?

Yes, of course it was. The packaging of the Eurolux LED is inexcusably devoid of technical information, except to say that it delivers 50 lumens, a rather useless piece of information for the average consumer. It turns out that 50 lumens is an equally useless amount of light, unless you are just looking for a decorative accent to highlight your teacup collection. A 50W halogen, the most common size of downlight, delivers about 10 times that much light.

Eurolux, a company from the Philippines—despite its name—has very good prices and is prominently displayed in many South African stores, but I do not trust their quality. I have seen too many Eurolux compact fluorescents fail while major-brand CFLs continue burning brightly. I buy almost all of my lighting supplies from Osram and Philips, and I believe the premium I pay for those brand names is compensated by their durability. (Eurolux, like Philips, does carry a three-year guarantee on their LED products; Osram LEDs are covered by a five-year guarantee.)

LEDs are falling in price, but for now, expect to pay R300 and up for a good-quality bulb. That may seem like a ridiculous price for a globe, but depending upon where it is used, LEDs can be a financially sound investment. According to Philips, Makro Woodmead and Strubens Valley and Pick N Pay Faerie Glen currently sell a 7 watt Phillips Master LED GU10 bulb for R299. My calculations suggest that over the course of 4 years, in a room where the lights are on 5 hours a day, this LED bulb is no more expensive than buying and using the equivalent 35W halogens at R40 each. After those 4 years, the LED pays a return on your investment. (The calculations ignore the cost of capital. You wouldn’t charge the environment interest, would you?)

If the bulb is in a location where it burns less frequently, it takes longer to pay for itself, and vice versa. At 3 hours a day, expect a 7 year payback; at 6 hours, the initial outlay is recouped in just 3 years. LEDs are improving rapidly, so the temptation is strong to wait. My advice is to buy a few now for a room where the lights burn longest, and gradually add more rooms as better and more affordable LEDs become available. Sometimes you have to spend a little to save a lot.

GeyserWise . . . . . . not saving in Power Save Mode

As far as I’m concerned, my GeyserWise thermostat timer paid for itself within a few weeks. Then it started costing me money.

The GeyserWise is an electronic device that replaces both a timer and the thermostat on an electric geyser element. As I have stated before on this website, a timer is an essential part of a hot-water solar system. The GeyserWise would appear to be the ultimate geyser timer, allowing the user to set multiple programs to turn the geyser element on and off, to see the temperature inside the tank, and to adjust the thermostat setting from a comfortable position several meters away from the geyser itself. No more crawling into the roof space with a headlamp and screwdriver.

I paid R1300 for my GeyserWise, including installation by an electrician recommended by the manufacturer. Here’s how it paid for itself so quickly. Monitoring the temperature inside my tanks, I started noticing that the water would cool off by a few degrees in the late afternoon every (more…)

Chris Yelland and the team at EE Publishers are the gurus of all things to do with electric power. So all South Africans would do well to pay attention to their analysis in this morning’s EE News: Brace yourself – the electricity price trajectory for years to come…
The article makes the point that when the National Energy Regulator of South Africa nixed Eskom’s proposed annual rate increases of up to 35 percent . . .

Many consumers breathed a sigh of relief, but a fact that received little attention at the time was the indication by NERSA that the 25% p.a. increases allowed for 2010, 2011 and 2012 would now likely continue after 2012.

The article later adds:

Irrespective of which scenario is considered, the projected electricity prices in the draft IRP 2010 show annual increases well above inflation up to 2021, and it would appear that the golden era of Eskom price increases at or below inflation will only arrive thereafter.

And concludes:

. . . take heart! Electricity prices should level off in about ten years time. Highlight 2021 in your diary as the dawn of a new era of Eskom price increases in line with inflation. Maybe…

I ran some of these numbers through a spreadsheet to see what they might mean to my electricity bill. For Eskom to reach the prices it originally envisioned before NERSA put a lid on annual increases, 25 percent price hikes will have to continue to at least 2014. Assuming that City Power of Johannesburg passes these increases on to residential users, this means that the 68 cents per kilowatt hour we pay today could leap to R1.66 in the next 3 years.

I don’t raise this issue to increase anyone’s blood pressure. What interests me is that this information completely changes any cost-benefit analysis of investments in energy efficiency at home. Back at my spreadsheets I find that  a solar hot water system that would pay for itself in 5 years at 68 cents a kilowatt hours, recoups the outlay in just 2 years at R1.66 a kilowatt hour. An efficient, variable-speed pool pump that makes sense as an investment over 7 years, suddenly makes much more sense by turning profitable in just 3 years.  LED lights that were expected to cover their costs in 6 years achieve that mark in 2 1/2 years.

I don’t think that every effort to make a greener house has to pay for itself. A little bit of financial analysis does help point out the changes that can make the greatest impact for the least expense, however. Eskom may not be doing our budgets any favours, but it sure is turning the cost-benefit analysis for eco-friendly investments green.

When I first wrote on GreenerHouse about dishwashers, I lamented that I could not find one with a hot-water inlet. For most of the year, I have an excess of solar-heated hot water sitting in tanks, so it is a waste for my dishwasher to be electrically heating cold water. At the time, I had been misinformed by a Bosch technical expert that the inlet to my dishwasher could handle a maximum of 40 degrees. Like an idiot, I hadn’t read the manual, which says that the inlet can take up to 60-degree water.

Water heated by flat-panel solar collectors does not tend to rise much above 60 degrees, and my kitchen is far—too far—from my water tanks to ever get to 60 degrees at the tap, according to my thermometer. (Vacuum-tube panels do often produce much hotter water, and may require a thermostatic mixer to keep temperatures at safe levels.)

So I recently asked my plumber to connect the hot water to my dishwasher. My hypothesis was that the thermostat inside the dishwasher would switch off the heating element more quickly with warm water entering the machine. Using a cold-water feed, this Bosch, A-rated model uses approximately 1 kWh per load at the 35 degree “Quick Wash” setting. After connecting the hot water, I recalculated the energy consumption, using the technique outlined here. It has fallen to 0.7 kWh per wash. Over the course of a year, this simple change should save about 100 kWh preventing some 100 kilograms of carbon dioxide from being released into the atmosphere.

If my dishwasher were located closer to the hot water, the savings would be far greater. In designing a new house, ideally the north-facing roof, solar panels, hot-water tanks, bathrooms and kitchen should all be as close as possible. If this is not possible, small-diameter Pex pipes can help overcome heat loss over long distances. (Combining Pex pipes and vacuum-tube solar collectors is asking for a meltdown, however.)

I compensate by running the hot water in the sink, usually while washing pots and pans, immediately before switching on the dishwasher. That way the water enters the machine hot for the wash cycle, though only slightly warm after the copper pipes have cooled the water for the two rinse cycles. One day I will try insulating the pipes and see if I get even better results. In the winter, when the sun does not always provide enough hot water, I will try to run the dishwasher in the late morning, so as not to deplete the evening supply of hot water.

Coincidentally, just days after my plumber had made the connection and before I had a chance to measure my results or write about it, a GreenerHouse reader published a comment here, reporting how pleased he was with his hot-water connection to his dishwasher. All green minds think alike.

Throne contender Venezia

Long ago on this website, I gave my seal of approval to the Compact dual-flush toilet made by R.A.K. Bathware. (And blew a raspberry at a dual-flush toilet that does not work as advertised.) For nearly 6 years now, my R.A.K. Compact has flushed dependably well over 9 times out of 10, for both 3 litre half flushes and 6 litre full flushes. I had no expectation of finding a better toilet.

Over the holidays, however, I stayed at a house that had recently fitted Venezia toilets by Lecico, an Egyptian company. Using seemingly insignificant amounts of water, these toilets made absolutely perfect flushes. They were so perfect, in fact, that I sometimes flushed . . . uhhh . . . “solids” using the half flush. Officially, the Venezia is a standard water-saving toilet, using no less than the Compact, but this would depend upon the settings of the mechanism inside the cistern. I am certain that these Venezias were using less than 6 and 3 litres per flush.

This gives me some confidence that Lecico’s ultra-efficient Riviera toilet, rated to use just 4.5 litres for a full flush and 2.6 litres for a half flush, will function properly. The Riviera is also more attractive than the Venezia. But just to be clear, I have never used a Riviera and make no promises for it.

I priced all three of these toilets at Plumblink, and the Lecico Venezia is the cheapest of the lot. Packaged with a basin worth a few hundred rand, it costs R1175, excluding VAT. For the toilet alone, the R.A.K. Compact goes for R1139 and the Lecico Riviera will set you back R1195.

These figures are rather small next to the savings you can expect on your water bill. If you are replacing an old 9 litre toilet, a family of 5 could save about R625 every year at current Johannesburg water rates, R780 if you regularly water a large garden, bumping your bill into a higher tariff. Heavy consumers paying Cape Town’s higher rates would save over a thousand rand each year.  Our dual-flush toilets have already paid for themselves more than once.

By the way, most ordinary lever-handled mechanisms can work as a sort of dual-flush mechanism with a deft touch. Simply lift the lever back up part way through the flushing process for a D.I.Y. dual flush.

The early summer cold-front that has been chilling Johannesburg for the last few days has me scratching my head. I measure my electricity consumption regularly and record it on a spreadsheet, and suddenly found that the household’s daily usage had jumped from about 15 kilowatt hours to about 25. Then we ran out of tea just a few days after we opened a box of 80 bags. Could there be a connection? Four children are at home studying for exams in the cold, and teacups have been piling up on their desks. With a thermometer, a stopwatch and a calculator, I set out to solve this mystery.

To raise a litre of water by one degree Celsius theoretically requires 0.0011 kilowatt hours, so heating my 1.7 litre kettle from tap temperature to boiling, 17 to 97 on my thermometer, should use 0.15 kWh. But since it took 3:48 to boil while using approximately 2750 watts, the actual consumption was more like 0.175.  (My Watts Up meter cannot handle appliances over 2000 watts, so I could not measure directly.) The inefficiency probably comes from the heat lost warming up the stainless-steel kettle itself—a plastic kettle might reduce those losses—and the delay between when the water reaches boiling and the kettle shuts off.

Of course, they don’t all share a pot of tea at once, so I used a spreadsheet to simulate two scenarios. In one, my children have suddenly become green angels, and measure out exactly one mug full of water into an empty kettle to boil. Under these ideal conditions, their additional 24 cups of tea a day would use just 0.59 kWh. The worst-case—and very common—scenario is to fill a kettle and boil it over and over again  until nearly empty before repeating the process. Under these circumstances, those same 24 cups of tea use nearly three time as much electricity, or 1.61 kWh. (Even after taking into account the warm water that is being re-boiled.)

My mystery is not entirely solved. The kettle could account for a sixth of the increase, but the rest must come from addition lights burning at desks, the refrigerator door opening and closing for study snacks, and those electronic devices that seem to take over study breaks.

Still, I’ve learned something useful. Changing kettle habits can make a significant impact on consumption. The Eco-Kettle is designed to make this simple, saving you from running back and forth to the sink to measure another cup of water. The water reservoir at the top of the kettle can release measured cups of water to the element at the bottom. It is available from a few sources in South Africa for R450 and up. Six people drinking 4 cups of tea a day with a full-kettle habit to break could probably save enough to pay for the expense in a couple of years.  I’ve seen a few complaints on the internet about durability, however, and I wonder if a simpler solution wouldn’t suffice. I plan to put a water jug next to the kettle and ask my family to measure out the water in their teacup before pouring it into the kettle. (Our kettle has a flat bottom. If yours has a raised element, it may need extra water to cover the element.) It should save them time, too. My stopwatch tells me that a cup of water boils in 51 seconds. A full kettle takes nearly 4 minutes.

While on the subject of kettles, I sometimes use ours as a back-up geyser. I try to keep the electric elements in my two, 300 litre solar-heated geysers switched off, and most days I don’t need them. But occasionally I have been seen pouring a few kettles full of boiling water into a bath on a winter night to keep my wife from grumbling about my solar fanaticism. This causes her to ask, “wouldn’t it use less electricity just to turn on the element in the tanks for an hour?” My spreadsheet provides the definitive answer. Boiling even five kettles of lukewarm water from the hot tap uses 2/3 of a kilowatt hour. The 4000 watt element on the geyser would use 4 kWh in an hour. There are times when a full kettle is green.

95 right? More likely wrong.

The conversation after Sunday lunch somehow migrated to the topic of octane in petrol. A woman was complaining that her husband makes her buy premium 95 petrol even though it costs more. The husband, who drives a Prius, was defending the extra expense on the grounds that the extra octane makes the engine run more efficiently, reducing carbon dioxide emissions.

I had never heard this before, and any idea that might reduce C0₂ emissions catches my ear. Was I unwittingly damaging the atmosphere by my frugal habit of buying the cheaper petrol? I had to look into this.

One of the best sources of information available was an Engen FAQ on octane, which confirmed, as I had suspected, that we cheapskates are right. “The great majority of vehicles inland . . .  are satisfied by 93 octane,” the website explains. “The use of octane grades higher than your vehicle actually requires will cost you more, cost the country more and have a negative environmental impact.”

The FAQ explains that this is because:

“There will be no additional benefit to driveability or performance of your vehicle if you use a higher grade than it requires. Petrol with a higher octane requires more severe refining and greater energy use in the production process. If not offset by greater fuel efficiency of the vehicle using the fuel, this extra energy use is wasted energy. This wastage results in higher emissions of greenhouse gas (carbon dioxide), which harm our environment.”

What the Engen website did not explain is the relationship between octane and altitude. Octane is purely a measure of how petrol reacts to pressure. Higher octane fuels will not ignite prematurely under higher pressure, which could cause engine knocking. But the Highveld altitude has a low ambient air pressure, which reduces the pressure inside most engines and thus reduces the need for octane. I spoke to John Fitton, an independent petroleum industry consultant, who said that most engines requiring 95 octane at the coast—as is recommended in the manual for my Honda Jazz—only need 91 octane in the Highveld.

South African regulations allow for three grades: 91, 93 and 95. At low altitude, 95 is the only grade available. Highveld petrol stations offer 93 and 95, but 91 isn’t sold at all in South Africa. Fitton told me that this is only because the petrol retailers are trying to satsify ill-informed customers. “Consumers think octane is power,” he said.

Fitton pointed out that the lower octane requirements at higher altitude do not apply to turbocharged engines and a minority of newer engines with gasoline direct injection. (These engines are sold under a variety of brand names such as Mercedes-Benz’s Charged Gasoline Injection, VW’s FSI and Ford’s EcoBoost.) Owners of these cars should obey the instructions in the car manual whether they are in Lesotho or Lambert’s Bay. For the rest, Fitton said, “There’s no advantage to using the higher octane; you’re just going to spend more money and emit more C0₂.”

White lies, palm-free

The other day, my daughter asked for help with a school assignment that required her to write a list of things she could do to prevent deforestation. Her list already included some obvious items to do with saving or recycling paper, but she needed more. I explained that because tropical forests are being ripped up to make way for palm-oil plantations, some people are avoiding products made with palm oil, such as Dove soap. “But Dad,” she protested, “then why do WE use Dove soap?”

Why, indeed? Lacking enough knowledge about the alternatives, I had allowed our family to stick with this old habit. I knew that the main culprit in the expansion of the palm-oil plantations was biodiesel for the European market. But significant quantities go into soap and foods, so it was worth looking for alternatives. These proved to be difficult to find. In my local Pick n Pay, every bar of soap had either sodium palm kernelate, sodium palmate or sodium palmitate on its list of ingredients. Liquid soaps never have these ingredients, but they come in wasteful, disposable pump packaging. (They also probably have other unsavoury ingredients, but I already steer clear of antibacterial soaps and I’m just trying to save the rainforest for now.)

The trick seemed to be finding a bulk refill liquid soap so that I could keep reusing the pumps that are already in my house. Single-use refills invariably come in unrecyclable pouches, so they’re not particularly helpful. I never found bulk hand soap in any ordinary store, but a factory shop near my home carries five-litre containers of Plush Pearly Lotion Soap. It has no list of ingredients and I have no way to verify the “biodegradable” claim on the label. I am confident that it contains no palm oil, however. It may not have a particularly exotic scent or produce the most luxuriant lather I’ve ever come across, but it works very well. I quietly placed it in every bathroom and shower in the house, and no one has even noticed. And at R94.50 for five litres, I calculate that it costs one-quarter the price of single-use pumps by volume. So saving the rainforests is saving me a few rands to put aside for a rainy day.

Lights out for cold

When the water began pouring out the door of our ancient washing machine onto the kitchen floor, I finally accepted that it was time to buy a new one. During a previous, failed round of shopping for a washing machine, I was put off by all of the conflicting claims about the efficiency of different washing machines and the confusing range of options. Did I want steam cleaning? Would a hot-water inlet save electricity? But I relaxed when I realized that none of these complications really matter. Any washing machine with an A rating from the EU will be relatively efficient in its use of water. And if you wash in cold water, electricity consumption is practically a non-issue.

I discovered to my surprise, however, that this revelation does not suddenly make choosing a washing machine simple. At the first appliance store I visited, the basic Bosch washing machine that I wanted to buy did not have a cold-water option. The lowest temperature allowed was a warm 30 degrees. To buy a Bosch machine with a cold-water option, I would have to pay R2,700 more. The basic machine is efficient, with an A rating, but even at the lowest temperature setting, I would at least double my energy consumption compared to my old, inefficient machine on cold.

I also encountered a lot of resistance from salespeople about cold-water washing. The usual line is that the washing powders work better in warm water. This may be technically true but practically irrelevant. What I know is that in any line-up at school, my children’s white socks and white shirts look brighter than most of the others. My theory is that any advantage warm or hot water may have in removing grime is countered by the grey tinge that the whites pick up from colours that bleed, even if the wash is largely separated into light and dark loads. Besides, the latest Skip packaging says “works just as well in cold water.” The fact that our washing dries in the Highveld sun also makes it brighter than tumble-dried laundry.

At another store I did find LG and Samsung machines that allowed independent temperature settings, including cold. Both LG and Samsung get top marks for their washers in recent quality ratings by J.D. Powers. I chose the Samsung because its dimensions fit better under our kitchen counter.

I wish I could say that my new Samsung washer (model WF8500NHW) is the ultimate choice for cold-water washing, but I have encountered two disappointments in using it. The first is that each time I turn the appliance on, it resets to 60 degrees. I must remember to change it to cold before each wash. The second is that on one useful wash cycle, synthetics, it refuses to go to any temperature other than 40 degrees.

These obstacles are surmountable. We have become accustomed to washing on the longer, cotton cycle and resetting the temperature each time. My Watts Up meter tells me that I’m using less than 0.2 kilowatt hours per wash, which is a fraction of the consumption for a hot wash in the most efficient machine available. But I would advise anyone in the market for a cold-water washing machine to ask a lot of questions or watch a machine in action before handing over your money.