Let The Sun Shine

The Jakarta Post - WEEKENDER   |  Tue, 05/19/2009 6:51 PM  |  Greenlifestyle

The other day someone came up to me and asked a question that any self-respecting greenie should be prepared for: “How exactly do you install one of those solar panel things?” followed by the fatal blow: “And will it bore a hole into my wallet?”

We’re going to skip the whole part about how I got out from that conversation with my eco-dignity unscathed, and fast forward to a few days later when, after having brushed up on my kilowatts, insulation values, inverters and Amperes, I decided to put it all on the back of the proverbial envelope.

Here are the basics for going solar.

Tap into that bright, free stuff

First, you need a good reason to go ahead with the plan. Among the many wondrous things that Indonesia has in abundance is free sunlight. For many reasons which we’re going to conveniently set aside for the time being, we have used little of this resource so far. Instead, we extract copious amounts of coal, which is burned at great environmental and economic cost, to make electricity. Burning coal, as you may have heard from Mr. Gore, does some really nasty things, including contribute copious amounts of carbon emissions into the atmosphere.

For scientists, power generation is one of the prime suspects for global warming. As energy needs continue to grow in Indonesia (I suspect 90 percent of this is driven by sinetrons), the demand for coal keeps increasing. Power plants are struggling to keep up with demand; when they can’t, the switch is flicked off and a few million people are left reaching for candles.

Now what if we could do without coal? Solar panels are a shimmering promise of a future where you could draw free energy from the sun to power everything from your fridge to your VCD player. The problem, as usual, is that there is an upfront cost to install the system. Depending on your power needs and the reliability of your electricity, a solar panel may not be an affordable option for you. Friends, there is only one way to find out – do some math.

A blueprint for your home green power plant

1. Make a quick list of your home electricity needs, ranging from light bulbs to appliances. One easy shortcut around this is to pull out your last electricity bill and jot down your kilowatt per hour consumption. For the sake of this exercise, let’s say that your electric appliances total 250 watts.

2. Next step. Assuming you want to cover only part of your electricity needs with a solar panel system (hey, we can’t just write off PLN, can we?), how many hours of energy will you need? We’re going to opt for a reasonable 12 hours, which gives us 12 hours x 250 watts = 3,000 watts. Now, because the solar panel installation itself will consume 20 percent of the electricity it generates, we’re going to add 20 percent to our total electricity needs. This brings us to 3,600 watts.

3. We’re going to need batteries to store this wonderful free energy. For 3,600 watts, that will be four batteries of 12 volts each.

4. Now that we know how many watts we must generate each day to keep our teh botol chilled, watch CSI Miami AND light our desk as we pore over our tax return form (3,600 watts), we have also figured out how many solar panels we need. A handy 100 wp (watt peak) panel exposed to five hours of fierce tropical sunlight will provide 500 watts. As we need 3,600 watt, that means we’ll need eight panels. That, or give up on David Caruso and downsize to a more modest seven panels.

5. Now here comes the part where eyes roll back, tongues drop out and people flick over to a more interesting part of the magazine. So solar panel setups are expensive: about US$9–10 for each watt. For eight panels of 100 wp each, this gives us 800 watt x 10, or a rather intimidating US$8,000. Now let me explain why this is still a good idea.

Admit it, you’re not too fond of coal. Now that you know what the stuff does to the atmosphere when it is burned to create electricity (hi again, Mr. Gore), are you still willing to depend on it exclusively to power your house? By most measures, eight grand is a lot of money, but think of this in the long term. You will need electricity for quite a few more years, so think of this as a lifetime investment. And as most of us don’t have $8,000 lying around, you can start small. One solar panel hooked on your roof, providing enough power to light your bedside table – you just got yourself a new hobby.

Now talk of a cool conversation starter at your next cocktail party.

(Thanks to Antonius Widiarso at PT Dynton for his technical input)

Greenlifestyle is a community of urban dwellers in Indonesia with more than just a passing interest in adopting an environment-friendly lifestyle. From saving on electricity bills to getting the ultimate compost going, visit www.greenlifestyle.or.id or send an email to greenlifestyle@gmail.com to tap into Greenlifestyle’s tips and best practices. You can also join the mailing list at http://groups.google.com/group/greenlifestyle .

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