New BEE Ratings for Air Conditioning ~ steady improvement but a long way to go

From the beginning of 2104—and in line with past practice—the Bureau of Energy Efficiency (BEE) has updated their rating system for all appliances including lights, fans and air-conditioners. I’m only going to talk about air conditioners here because they are, by far, the biggest guzzlers of electricity.

Energy efficiency is calculated as a ratio of output Watts v/s input Watts. So, if a 3,500W (1 Tonne) air conditioner needs 1,200W to run, then the EER is 2.92.  Up to the end of 2011, that would have made it a 4-star machine. In 2012 and 2013, it would have been considered a 3-star machine. Today, that same machine will be considered a 2-starrer. So yes, as technology improves, the ratings are revised and made a little more stringent—which is how it should be. Have a look at the table below to get an idea of the changes.

BEE Rating History

BEE Ratings over the last few years

While this is good, it may not be good enough.  As this article shows, the entry level for a single star is on par with many other countries but the higher ratings are somewhat below world averages.  Also, manufacturers of inverter air conditioners have long been saying that their machines cannot be rated because they are “better than 5-star”.  Checking the specifications for the ones available in India shows that many of them have an average EER greater than 3.5 but none cross 4.0 even for minimum cooling–whereas the same companies manufacture models for other countries with a higher EER.

This could be because of two factors:

  1. There is not enough incentive to go beyond the maximum available rating since the average person (and even most architects) won’t easily be able to compare two models for energy efficiency.
  2. Models with a a higher EER are more expensive to manufacture and the Indian market is notoriously price-sensitive.

While there’s not much anyone can do about the second factor, the first can certainly be tackled by raising the bar for ratings. As more and more people resort to artificially cooling their indoor environment instead of availing passive cooling (thanks to current architectural trends) our energy situation is getting more and more precarious.

I must be an idiot ~ or eccentric at the very least

crackpot environmentalist architect

The Crackpot Environmentalist Architect

Just received a call from a gentleman who wanted to develop 9 acres of land at Nasrapur village in Karjat, very close to some of the bungalows I’ve done and am doing there. That sounded interesting, naturally.

Unfortunately he wanted to make houses entirely and exclusively out of prefab steel. Never mind that they would not be environmentally sustainable and, therefore, contrary of the kind of work I do; never mind, even, that they might look like factory sheds! Someone had obviously convinced him that this was the way to go.

I said that I could not take up a project if I felt it was ecologically damaging and urged him to at least consider other options. He was closed to such crackpot ideas but very understanding about my foolishness. His words were, “Yes, of course, everyone has their… their own…” and then his voice trailed off.

Sometimes, it’s better to lose a project before you even have it in hand.

Micro Houses ~ when will I get to design one

A photo feature on unconventional tiny houses got me thinking about why we never hear of architects designing them in India.  Is it because a very small house is much too readily associated with poverty that we, as a country, are trying to leave behind? Or do we insist on big weekend houses on the off-chance that extended family and friends will come visiting and need to be accommodated?

tiny footprint

Micro houses have a tiny footprint

Whatever the reason, the concept of micro-houses is rarely considered seriously here–although it should be–because because they costs a lot less to build or maintain and, more importantly, they reduce our carbon footprint in a very big way.

We have a long tradition of frugal construction and it’s about time we rediscovered it. Maybe one day, hopefully in the near future, someone will ask me to design one. Or a bunch of them.

The Bottle Light ~ an inexpensive solution for lighting

bottle light refractionSometimes, a simple idea can be immensely powerful. Maybe the bottle light is not something that makes a huge difference to your life or mine but, for those who live in shanties with little or no electricity, this is a godsend.

screencap from a BBC featureEssentially, one fills a used, transparent, plastic bottle with water and a little bleach (to prevent algae) and sticks it into a hole in the roof.  That’s it. Oh, and don’t forget to seal the edges of the hole.

The light that it produces is equivalent to a 50 or 60W bulb. Of course it won’t work at night but when you think of the dark homes that some of our less fortunate citizens live in, this can—at the very least—brighten up their day.

BBC News Magazine
A Liter of Light

The Gaming of LEED Ratings ~ Bank of America Tower makes a mockery of platinum award

We all know that the LEED system can be gamed but that it could be turned so completely on its head was news to me.

greenwashThe Bank of America building at One, Bryant Park, New York has a LEED Platinum rating and was the first skyscraper to ever be awarded this but now, it turns out, it uses more energy per square foot than other building of similar size in all of Manhattan. Wow.

It was hailed as a major achievement by none other than Al Gore who set up his offices there. The basic problem is that LEED is largely based on computerised energy models and “intent”. This makes it open to abuse because it’s easy to purportedly intend something at the design stage and then change the goalposts later on.

Coincidentally, just this morning, I was speaking to a couple of marketing guys who were trying to convince me to attend a “green summit” next month and one of their selling points was LEED. I declined, telling them exactly what I thought of LEED but I wish I’d seen this article just a few hours earlier:

Bank of America Tower and the LEED Ratings Racket via: ArchRecord

Visit to ecobuild India 2013 ~ some stuff good. some, not so much

ecobuild 2013Yesterday was my day to visit Bombay Exhibition Centre at Goregaon for this year’s ecobuild India 2013.

I was a bit surprised to see some of the participating vendors because there was nothing remotely connected to sustainable architecture in their products.  Others, however, showcased more appropriate stuff.

Was disgusted by a company–which shall remain unnamed–that was promoting artificial thatch imported all the way from Thailand. Can greenwashing get more brazen than this?

On a positive note, I was impressed by products from Corvi and K-lite — coincidentally both are manufacturers of LED lights.  The former have a limited catalogue but all their fittings are dimmable with standard dimmers which is a major plus point in my book.

The show wasn’t very large but I presume it will grow over the years. I just think they should vet the products or else the show, as a whole, will soon lose credibility.

Glaring mistakes ~ another reason to reject glass façades

conventional v/s curtain wall

In hot climates, the overall energy usage rises as you increase the glazed area. Curtain walls, therefore, are highly inappropriate.

I have ranted about glass façades for a long time and this editorial by Sunita Narain of DTE has inspired me to add a couple of paragraphs to the original one.  Among other things, she has written about a recent study by IIT-Delhi which found that, in our hot climate, the manufacturers’ claims of special coated glass or double/triple glazing being able to reduce heat gain are rather hollow.

One of the other specious arguments put forth in an attempt to portray glass curtain walls as green systems is to say that it reduces the electricity consumed for lighting. This is a half-truth. Leave aside the uncomfortable glare that people working inside such buildings have to put up with, let us make s simple comparison.

Consider a 10m² conventionally designed space. Assuming that we don’t take passive cooling techniques into account, the air-conditioning load will be in the region of 3,500W (1 ton).  Lighting the same space, on the other hand, will need just 50W with fluorescents or 40W if we’re using LED fittings.

Now, imagine a similar sized curtain-walled space. The maximum saving that can be achieved by reducing lighting is a puny 50W. However–and this is the big problem–air-conditioning requirements will probably have risen to a whopping 5,000W.  Even with all the specially coated and multi-layered of glass in the world, the total requirement is unlikely to be anything less than 4,500W.

So yes, we may not use as much electricity for lighting but, I’m afraid, the energy usage for cooling will go right through the roof and no amount of marketing spin can get around this simple fact.

Building walls with the rat trap bond ~ they're really cool

Just in case I’ve got you visualising rodents scurrying about where they’re not wanted, ease your mind; the rat trap bond I’m talking about is simply a method of laying bricks when building a wall.  It’s similar to the common “Flemish” bond but instead of putting the bricks on their face, they are placed on their edges. This leads to cost savings because less bricks and cement are needed which, in turn, reduces the embodied energy of the wall.

The Rat Trap Bond

Bricks are laid on edge to create an air gap between two layers

Laurie Baker took every opportunity to try and make people realise the value of this method but, by and large, the 20-25% saving in brick doesn’t seem to have been appealing enough.  The rat trap method of construction was popular in England until the start of the 20th century but sustained lobbying by the brick-making industry convinced people that that it was not strong enough to build load-bearing walls.

That is rubbish of course; it’s strong enough for one and two storey buildings as has been proven over and over again by Laurie Baker’s lasting work. But masons too are not usually happy about adopting this system and come up with all sorts of excuses to try and avoid it. I have to admit that, till date, I have not pushed hard enough against their inertia but now I’ve just got one more reason to do so.

For the ShKo bungalow at Karjat, I plan to use the rat trap walls and wanted to know just how much difference they would make thermally. Nobody seems to have done a calculation of the difference — at least there was none that I could find. So, armed with some data from thermal calc and the energy evaluation component of ArchiCAD, I tried to do just that.

Taking just a simple 3m x 3m structure with no openings, I ran a calculation for both types of wall. Result: average U-value of the structure’s outer shell dropped about 15% compared to conventional walls and the energy required for cooling also fell by about 8%. The difference was exaggerated because the model had good roof overhangs to shade the walls.

Still, when you think about it, 8% is nothing to scoff at.  In addition, the embodied energy is reduced quite dramatically and, of course, Laurie Baker’s original reason for using the rat-trap bond still stands — the wall is simply cheaper to build.

Now, I just have to go and steam-roll the masons into learning a new technique.

ShKo Bungalow at Karjat ~ design completed

The design for the ShKo bungalow at Karjat has finally been completed. It’s taken a lot longer than most because, apart from the complex slope, there was a severe constraint of building within a small portion of the entire one acre plot — the rest is prone to occasional flooding from the adjoining river.

Like other architectural designs, this too makes maximum use of local materials and of passive cooling.  External stone walls are at least 24″ (60cm) thick and provide a formidable barrier to heat-gain even in a place like Karjat.  Deep verandahs on the South and West don’t allow direct egress of strong sunlight from mid-mornings till evening. And high roofs with openings at upper levels allow constant ventilation to take place.

Rainwater harvested from the roof will be collected in the basement that is automatically formed by the sloping land. It will also be used to flood the pool which will not, hopefully, have any chemicals used to disinfect it. The current plan is to do natural filtration but the eventual system will depend on getting a reliable and qualified consultant to carry this out.

View from the gate

Picture 1 of 5

The entrance is set within a recess adjoining the car-port. Deep roof overhangs protect most walls from direct heat-gain. All external walls are at least 24" (60cm) thick and made of local stone to keep the interiors cool even in summer.