Tag Archives: energy

Environment, Lifestyle

Residential Solar Power System Upgrade

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Last week we upgraded our solar power system for our home. Since we live off-the-grid in Hawaii, this was a major cause for celebration, which included dancing and lots of toasting well into the evening.

We now have a 48-volt system with 1600 Watts of solar panels on the roof. We also have 8 – 420 amp-hr batteries for storage and a 3 KW inverter.

With regard to how common off-grid living is in Hawaii, it’s mixed. On-grid is typical on Oahu, Kauai and the resort areas of Maui and the Big Island. Off-grid is more common on East Maui and the rest of the Big Island.

Here’s a run down of what we did:

  • Installation of two new 175W SW 24 Volt solar panel modules, bring our tally on the roof up to 1600 watts.
  • Connection of existing solar array strings to fused PV string connector.
  • New wiring to charge controller.
  • New MS60 Outback charge controller.
  • 8 L16 High capacity 420 AH batteries
  • New battery connectors 2/0
  • Concrete slab 20″x 55″ for batteries
  • Plywood enclosure for batteries
  • Plywood cabinet for Outback 3048 sine wave inverter. (SEXY describes it well!)
  • Indoor meter to monitor battery status and Voltage or Amp draw.
  • 110 Volt Flojet pump. This replaced our old 12 Volt pump, meaning we have better water pressure now, too.
  • All wiring below the string connector enclosed in conduit.
  • New conduit run with #6 wire to house in back.
  • Connection of house in back.
  • New main breaker cabinet next to inverter.
  • Removal of old batteries and equipment.

The total cost of the upgrade (i.e., ripping out then entire old system, save a few solar panels on the roof) was about $11,000. With the cost of grid energy in Maui hovering around 40 cents per kilowatt hour, this upgrade pays for itself in three years. If the price of diesel fuel keeps rising, the break even day will come even faster. There are also the environmental benefits of not spewing diesel fumes and CO2. And by not erecting power lines, we preserve the amazing ocean views. Here’s to solar power!

Environment, Family, Lifestyle

How To Choose and Use a Clothesline or Clothes Drying Rack

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Summer is here, and abundant sunshine makes it easy to save electricity and money by using a solar clothing dryer (aka a clothesline or clothes drying rack). Here are a few tips to get you started drying your clothes naturally and for free. In the process, you may come to love that fresh, out-of-doors scent that only comes with drying in the sun.

Line or Rack?

Clotheslines

There are many modern variations of the old-fashioned strung between two trees. If you have a large outdoor space and two trees, by all means go for a clothesline. This is a time-tested method.

Clothes Drying Racks

Chances you have an apartment, condo, deck or small yard and need to figure out how to use a tight space most efficiently. You may also need to adjust for season. If so, there are lots of great options available.

Racks are great for tight spaces and work both inside and out. There are many variations, but basically, racks consist of a wooden, aluminum or stainless steel frame with lengths of coated wire strung between the legs (or arms). When choosing a frame, consider where you’ll use it, indoors or outdoors, as well as cost. Stainless steel is typically more expensive than wood and more durable.

Racks can be freestanding, wall mounted, ceiling mounted or pole mounted; foldable, retractable or telescoping; and range in size from small enough for a single sweater mounted in a shower stall to large enough for a load of sheets in the yard.

Many excellent resources for clothes drying racks come from Europe and Australia, where apartments tend to be small, energy expensive and people more conversation minded. Shipping will be an additional cost, but one to factor into getting the right rack for your space that’s going to last. Here are just a few starting points (BTW, I have no commercial affiliation with or endorsement of any of these sites):

Pre-Drying

One handy gadget that I came across recently is a spinner (up to 3200 rpm) that dries clothes to slightly damp. It works like those machines at the gym, which spin down your wet bathing suit so you can take it home without soaking your bag. The same concept applies to laundry. A spinner could be very handy in tandem with indoor drying racks, in humid climates and during questionable weather. Treehugger.com has an informative post on these.

Hanging

There is an art to hanging wet clothes on a line or rack. They key is to strike a balance between the maximum number of clothes and the minimum amount of drying time. Here are some key points to keep in mind:

  • Don’t crowd the clothes. The more exposed each piece is, the faster it’ll dry.
  • Overlap the edges of shirts, towels and linens to save space (and clothespins)
  • Dry jeans upside down. The waist dries faster with more air flow.
  • Use a tie hanger to dry socks and underwear. You’ll save space and keep them from flying away
  • If indoors, open the windows for more air flow.
  • Take advantage of existing space, like benches, patio chairs, shower curtain rods and towel bars, to spread out the load.
  • Store clothespins in a bag inside to keep them clean. Dirty or rusty pins make for dirty or rusty clothes.
Environment, Family, Lifestyle

Solar Powered Cooking Oven

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Solar cooking ovens are an inexpensive and easy way to make every day Earth Day. Since I have owned mine, I have experienced lower energy bills, reduced carbon footprint, a cooler kitchen during summer, set and forget cooking and delicious tasting food. They are inexpensive, low-tech and downright amazing.

I live on solar power (“off grid”) and recently asked my in-laws for a new solar cooking oven as my Christmas gift. I initiated my new solar oven with a batch of dark chocolate brownies. The oven works better than I expected.

There are many good brands of solar cookers on the market that range in price from $100 to over $400. My solar oven came from Sun Oven and cost about $300. It was really simple to set up and very easy to use. Like regular ovens, you can use a solar oven for cooking, baking, braising and heating water. It will heat up to 450 degrees.

Set Up

The first step is to unfurl the reflectors and secure them with the built-in pin. Next position the oven so that shadows fall evenly on both sides. Look closely at this picture below. The shadows are not even on both sides. A quick adjustment of the oven to the right would even out the shadows, causing more direct light and a higher oven temperature.

The second step is to adjust the tip-tilt angle of the oven. For this adjustment, you will need to consider the overhead angle of the sun. At higher latitudes, the sun is typically lower in the sky at noon than at lower latitudes. Here in Hawaii during the summer, the sun is almost directly overhead so tipping is not needed. But when tipping is needed, there is a swivel pan inside the oven that conveniently levels itself.

To recap, simply unfurl the reflects, position the oven so that the shadows are even on both sides and tip the oven to match the overhead angle of the sun. The built-in thermometer will gauge the heat as you make adjustments.

Set and Forget

For quick recipes, like brownies that take 30 minutes or less, you can set the oven and forget it. As an devoted foodie, I have been nothing but delighted at how the food tastes – it’s more moist and tender. A solar oven is ideal for braising meats and baking breads. It’s easy enough for children to use, too.

One key accessory is a non-reflective pan, such as one made of glass or cast iron. For baked goods, like brownies, I use a glass pyrex pan as shown below. For meats, soups and stews, I use a cast iron dutch oven.

Plus, the solar oven doesn’t heat up my house. On a hot summer day, it’s possible to use less energy (and save money) by avoiding the conventional oven and extra air conditioning. In Hawaii where our electricity rates only increase, a solar oven will easily pay for itself within a few months.