Posts filed under ‘Basics’

Definitions and other matters

Once again, while wandering on another social media site, I ran across a question that needed answering. This time, someone wanted to know why hydrogen was never mentioned as a renewable energy source. As I wrote a response to this individual, I realized that there is significant potential for confusion and incorrect thinking around all of these terms that are thrown around today for various energy sources.

Baseload Power – Power that is generated pretty much continuously. Electrical use goes through peaks and valleys over time periods, baseload is that minimum power level that is pretty much always demanded. Most utilities will define different baseload levels for summer and winter. This seems to be a concept our FERC chairman, Mr. Wellinghoff, does not grasp. Baseload power is usually generated by the least expensive source available to the utility, but supply must be highly reliable. The three sources most commonly used for baseload power today are coal, nuclear, and hydro. Some regions use oil.

Low Carbon (Carbon free) Energy – Those sources of energy that emit little or no carbon dioxide (CO2) in the generation of energy. There is significant disagreement over how to tally the carbon impact of each energy source. Usually, it depends on the agenda of the author of any given study. Most agree that all hydrocarbon sources are NOT low carbon energy sources. All others can be considered low/no carbon sources. This includes geo-thermal, hydro, nuclear, solar, and wind. There are several more under development that may be added to this list.

Reliable Energy – Energy sources that can be relied on for consistent power generation over long periods of time. These sources are frequently considered for baseload supply. This term is not used as frequently because in the developed world, energy reliability is inherently assumed. However, as we consider new energy sources, reliability becomes important. For this article, I will assume reliable energy must be available > 75% of the time. Reliable energy sources today are coal, nuclear, hydro, oil, natural gas, wood.

Renewable Energy – These are those sources of energy that are either easily regrown, or are constantly available. Renewable forms of energy include, ethanol, solar, wind, hydro, geo-thermal, wood pellets. Renewable energy is perhaps the most misunderstood phrase in the energy pantheon. Many people believe that renewable implies ecologically sound, sustainable energy. This is not the case. Ethanol and wood pellets both are sources of atmospheric carbon, both are also not sustainable in the long term. Ethanol is currently made using corn. This places food and energy production in direct competition for land and resources.

Sustainable Energy – Those sources of energy that can be used long term with minimal total impact on the environment and without depleting the fuel source. Most consider this the intersection of renewable and low carbon sources. Typically, solar, wind, and geo-thermal are considered sustainable energy sources. Arguments for nuclear, hydrogen, and hydro are also quite compelling.

I hope that by spending a few minutes reading these definitions, I have provided some clarity to these discussions.

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May 8, 2009 at 1:09 pm

Solar Panels – the math

On another social media network, the question was posed…”If every single rooftop in the country was covered in PVs, I’ve heard that we would generate enough electrical energy not to need any other source of electrical power! But, has anyone done the maths?”

The questioner was from the UK. Many people immediately jumped on the issue as a dumb idea because of many other logistical issues, but no one “did the math”. Anyone that knows me at all knows that I tend to “do the math” first then look at the resulting implications.

Basis and Assumptions:

On average the sun provides about 1000 watts per square meter (at sea level, higher as you go up in elevation, but a convenient number for my purpose…)

Current solar panels are currently less than 30% efficient. We’ll use 30% because it makes the math easier. We’ll add “windage” later.

Let’s be generous – given Britain’s famous weather – and say you can generate electricity from all panels at this peak efficiency for 10 hours per day, 365 days a year.

Current consumption in UK is nearly 400TwH per year.

The Math

Solar panels (at 30% efficiency) generate 300 watts per square meter. So for each hour of sunlight, they generate 300 watt-hours or 0.3 KwH.

Over a 10 hour period, each square meter of solar panel can generate 3 KwH of electricity. Over the course of a year, each square meter could produce just over 1 MwH of electricity.

To generate 400 TwH of electricity would require almost 400 square kilometers of solarpanels.

If, on the average, one could put 2 square meters of PV’s in the most optimal south facing position on the roof of a building, then you would need 200,000,000 buildings.

Given my rather positive assertions related to both efficiency, and available sunlight, I would double that for a realistic scenario. SO, you would need to put PV’s on 400,000,000 buildings

Conclusions

Solar panels are not a panacea that will solve all of our problems. My scenario above ignores the complex grid and energy storage structures that would be required to move electricity from such a dispersed generation to concentrated population centers and industrial applications and storing summer generation for use in winter. I’m sure any utility engineer could add dozens more considerations that I’ve not mentioned.

I believe that all of the low carbon emission options must be explored and applied to the maximum extent feasible to lower both dependence on non-domestic sources of fuel and GHG impact on our planet. But, we must maintain a balanced application of all of these technologies in order to maintain a society we all want to live in.

May 6, 2009 at 1:00 pm 3 comments

A Parable of Power

A farmer in western Venezuela is tired of his intermittent electric power. For several hours every day he is without electricity. Why? Primarily because Venezuela’s government controlled electrical system is inadequate to the growing population. They have large hydro electric dams in the eastern part of the country, closer to Caracas, to the major population center of the country. But that power must travel across the country on an unreliable grid to get to the farmer’s property in the mountains above San Cristobal in the west. So, for several hours each day, the farmer is without power.

This is more than just annoying for the farmer. Because he has no centralized source for water, he relies on a local well for his water with a pump. When there’s no electricity, there’s no water either. If there’s not water, he can’t water the tender plants in his subsistence garden when the rains don’t come at the right time. He also can’t get water for bathing and cooking.

So what should this farmer do?

Well, first, he built some additional tanks to store water so that during these outages, he can water his plants, cook his food, and keep himself and his family clean. But still, this lack of power holds the farmer back. Unreliable power is a key contributor to his community’s inability to grow and develop. They cannot count on electricity to light their homes, heat their water, run their computers.

So what should this farmer do?

He decided to put in something to generate electricity whenever the government provided system failed. What should he install?

A solar array? He lives in an equatorial region high in the mountains, a solar array would certainly provide significant power, but only during daylight hours and not at peak efficiency when it rains (a frequent occurrence in this region). To install a solar array means that he must also install a complex battery storage system and inverters. He is not a technical person, this is more than he can manage.

A wind turbine? The wind blows down the valley to his home pretty steadily, but again, there is an inconsistency to deal with. Perhaps it would still suffice, at least most of the time, the wind blows sufficently.

A nuclear plant? Geo-thermal facility? Both require far more resources than the farmer has at his disposal, even his little community could not band together to build such complex facility. The Venezuelan government is giving serious consideration to a nuclear plant, but the time is years away.

So what DID the farmer do?

He installed a gas-powered generator. Why? Because the Venezuelan government subsidizes gasoline to where it costs about 5 cents/gallon. A generator is easily started when it is needed and can be run only when it is needed. It is a relatively simple mechanical system that the farmer and his community can maintain without a degree in engineering. At 5 cents/ gallon, fuel is relatively inexpensive compared to his income, so the operating costs as well as the initial installation costs are low.

So what is the lesson from this parable?

Ultimately, all of the “green options” failed for this farmer. Instead, he chose a technology that provided him with the needed power, in a way he could understand and manage. We, in the developed countries, sit in our heated and air-conditioned homes, with our computers, microwaves, and refrigerators and argue the relative merits of the low-carbon options that are available to us.

How do we change this conversation?

Added 5/5/09  This is not just a parable, but a true story, not something made up by me to provoke discussion. I personally know the farmer involved in making this decision. Some facts have been altered to preserve his anonymity.

May 4, 2009 at 11:22 am 4 comments

Reduce, Reuse, Recycle: Reuse Ideas

Last week, we talked about how “REDUCE” fits into the lives of “Practically Green” people. This week, let’s look at REUSE. REUSE is both the easiest and the hardest for those of us in the “practically green” lifestyle. We all get the concept of reusing things instead of throwing them away. BUT, so many of the ideas I’ve seen out there are either ridiculous in terms of time to remake the item (crocheting old shopping bags into a new shopping bag comes to mind – I tried it…) OR they are not items we actually WANT to have in our homes or on our persons (using old CD’s as coasters? – or converting a keg into a side table – a little too college dorm for my 50 year old tastes). This entry in my blog is going to be a simple list of great REUSE ideas that you can pick and choose from. I’m going to try to limit myself to items that require NO crafting skills, and insignificant amounts of time or instruction. More complicate ideas will be their own entries.

Reusing things? In OUR throwaway society? WOW! What a concept! How does this work? I touched on one easy idea last week as a part of REDUCING consumption. Shopping bags! In fact, these two concepts (REDUCE and REUSE) can be quite linked together. By reusing things, we are essentially reducing consumption of stuff. I try to think about REUSE as I’ve purchased something to perform some specific task, but instead of throwing it away afterward, I find another use for that thing. It’s all about reducing the amount of stuff getting sent to the landfill.

My mother was a small girl in Oklahoma during the depression. She remembers not having enough to eat every day and having to wear hand-me-downs from her older sister until almost the start of World War II. When I was growing up, she would make my lunch every day, I was expected to bring home the tin foil, and the paper bag for reuse until they were just too nasty. I was frequently picked on for this habit. Little did we know that my mom was just WAY ahead of her time when it comes to conserving resources. It turns out those little money saving tricks ALSO conserve precious resources.

Here’s my list. Feel free to add your own in the comments:

  • Margarine, sour cream or cottage cheese tubs for food storage. Need I say more? Do check the seal for the lid and make sure the plastic is microware safe before reheating your soup.
  • Water bottles refilled from the tap With Caution, most of those bottles are not intended to be refilled. I suggest only doing this for ONE day. Toss the bottle at the end of the day. BETTER IDEA: buy those bottles for your bike and fill them with filtered water. They can be washed and reused 100’s of times.
  • Shopping bags bad idea – except as small trash can liners or when you go to the grocery store. Frankly, almost all of the ideas I’ve seen look like you’re trying to use up shopping bags. If you’ve accumulated too many, take them to your nearest megamart, they almost always have a recycle bin for these. PLEASE don’t just throw them away. Bad for all kinds of wildlife when they start blowing around at the landfill.
  • Coffee mug I have so many coffee mugs. While I can give them to a second hand store, I suspect they don’t sell well. I think it’s better to find uses around the house. Let’s see: As a pencil holder on my desk (both at work and at home), as a small vase – especially the interesting ones. As a candy holder – potentially for a cute gift for those silly occasions where a small gift is needed.
  • Old tote bags and purses I’m talking about the ones that are a little too frayed for office or travel use here, not the ones the dog ate. One bag has become my garden equipment stash. Makes it easier to have all those little tools handy. Another is my mobile “to-do” paper stash. Has recipes, magazines, print-outs, etc that I need to look over and think about. Keep one in the car with car stuff that doesn’t fit in the glove box.
  • Print on BOTH sides of the paper We were astounded to discover that our run of the mill laser-jet printer could actually print on BOTH sides of the paper as a default. Turns out that many of them can. Look for “duplex” in the settings. 99% of the time, we can print stuff on both sides.
  • Paper towel cores – OK, I do have one or two uses that don’t entail turning these into Christmas decorations. I keep my silicone baking mat rolled up inside one these and stashed with my baking stuff. Also, during my big baking season (Christmas cookies, anyone?) I’ll stash parchment paper in a paper towel tube. (see the next entry)
  • Parchment paper – It can be reused 3-4 times before it gets too brittle and tears. Stumbled across this when I ran out and didn’t want to run to the store in the middle of my baking spree.
  • Shredded paper. Packing material. Skip the styro peanuts. It also works as mulch, but looks a bit strange on the plants…
  • Styro peanuts – Speaking of which… Most mailing and shipping places will take them from you instead of sending them to the landfill. OR, use them instead of rocks in the bottoms of your planters. They weigh a lot less and make the plant easier to move. Do test if your peanuts are Styrofoam or the new cornstarch based babies. Just run one under some water. If it disintegrates, you have cornstarch peanuts – put them in your compost pile or out in your garden and they’ll melt away.
  • Newspaper. Yes, it is recyclable, but far better to reuse it instead. Save newspapers if you are anticipating moving or storing breakables. The stuff the moving companies use is just “virgin” newsprint. Polish glass windows with it. Mom used to make me do this as a kid. Still works today.

Got some more ideas? Add a comment. We’ll test it and if it works well, add it!

February 16, 2009 at 9:55 pm 2 comments

Reduce, Reuse, Recycle: How to REDUCE?

Ok, The mantra for anyone claiming to know about (and write about) GREEN living, is “REDUCE, REUSE, RECYCLE”. Seems a pretty obvious phrase. Reduce what we use, Reuse what we can, Recycle the rest. The trick is, of course, in the application. There are some folks out there who have taken this to an extreme that the rest of us can only shake our heads at. They are living “off the grid” and growing their own food. The rest of us? Sorry, we have jobs to go to, kids to haul to soccer practice, and our favorite shows to TiVo. So… what does REDUCE, REUSE, RECYCLE mean to a “practically Green” person like me? That’s the whole point of this blog.

Let’s look at each work in this phrase and see where we can go with it.

REDUCE: hmmm, reduce what we use. Easy enough, but where to start? Let’s look at this another way. Reduce what we DON’T use. For us “practically green” types, the first step in REDUCE is to eliminate the stuff in our lives that we don’t use. Like… plastic bags for the groceries (and everything else you buy). It’s easy and in more and more stores, you get a rebate for bringing your own bags. In fact, I switched grocery stores because Mega-Mart #1 didn’t recognize my small contribution to the fight and Mega-Mart #2 gave me “in store cash” worth a nickel for every bag I brought with me.

A nickel?

Hardly seems worth it. Let’s put that in context of cost and benefit. First, you can actually REUSE (I know, the next article is on REUSE, but bear with me) the bags that you got the last time you went. I’ve found they survive about 3 trips before tearing out with the cheap lightweight variety. The heavier weight ones, (like from mega bookstores) will last numerous trips. I use on average 3 bags at the store each time. So, I get $0.15 USD for my effort, no time involved, and no expense.

Better option is to scrounge up those bags you’ve accumulated as give-aways for just being you. Without buying a single bag, I now have collected 7-8 cloth bags of various levels of sturdiness. I can put more groceries in each bag than the cheap plastic and don’t have to make as many trips to the car to retrieve the groceries. I’d say it’s a winner!

WORST case, you have to buy cloth bags. Your local mega-mart is probably selling them for $1USD each. Insulated bags for bringing home the Ben and Jerry’s might run $5. It will take only 20 trips to the store to pay for that regular bag at a nickel each time you use it. AND now you have a bag to use at the local farmer’s market, etc, etc. Hold the thought on the insulated bag – I’m not recommending purchasing that – I have a better idea. But that’s for another article!

But wait, there’s MORE! Now that we’re all thinking about ways to REDUCE consumption, or NONconsumption, where else can we REDUCE without actually giving up something? Consider…

  • Water in shower
  • Plastic water bottles
  • Keeping hot stuff hot (and cold stuff cold)
  • Unplugging the vampires- all of those power adapters that are plugged into the wall, but not into your cell phone (except when it’s charging)

What have I missed? Send in comments and let’s add more entries! As we get the articles added, I will come back and link them into this one!

Next post: REUSE

February 7, 2009 at 2:33 pm


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