Twice the height of the Empire State - EnviroMission plans massive solar tower for Arizona

 An ambitious solar energy project on a massive scale is about to get underway in the Arizona desert. EnviroMission is undergoing land acquisition and site-specific engineering to build its first full-scale solar tower - and when we say full-scale, we mean it! The mammoth 800-plus meter (2625 ft) tall tower will instantly become one of the world's tallest buildings. Its 200-megawatt power generation capacity will reliably feed the grid with enough power for 150,000 US homes, and once it's built, it can be expected to more or less sit there producing clean, renewable power with virtually no maintenance until it's more than 80 years old. In the video after the jump, EnviroMission CEO Roger Davey explains the solar tower technology, the Arizona project and why he couldn't get it built at home in Australia.


How Solar Towers Work

Enviromission's solar tower is a simple idea taken to gigantic proportions. The sun beats down on a large covered greenhouse area at the bottom, warming the air underneath it. Hot air wants to rise, so there's a central point for it to rush towards and escape; the tower in the middle. And there's a bunch of turbines at the base of the tower that generate electricity from that natural updraft.


It's hard to envisage that sort of system working effectively until you tweak the temperature variables and scale the whole thing up. Put this tower in a hot desert area, where the daytime surface temperature sits at around 40 degrees Celsius (104 F), and add in the greenhouse effect and you've got a temperature under your collector somewhere around 80-90 degrees (176-194 F). Scale your collector greenhouse out to a several hundred-meter radius around the tower, and you're generating a substantial volume of hot air.

Then, raise that tower up so that it's hundreds of meters in the air - because for every hundred metres you go up from the surface, the ambient temperature drops by about 1 degree. The greater the temperature differential, the harder the tower sucks up that hot air at the bottom - and the more energy you can generate through the turbines.

The advantages of this kind of power source are clear: 

Because it works on temperature differential, not absolute temperature, it works in any weather;
Because the heat of the day warms the ground up so much, it continues working at night;
Because you want large tracts of hot, dry land for best results, you can build it on more or less useless land in the desert;
It requires virtually no maintenance - apart from a bit of turbine servicing now and then, the tower "just works" once it's going, and lasts as long as its structure stays standing;
It uses no 'feed stock' - no coal, no uranium, nothing but air and sunlight;
It emits absolutely no pollution - the only emission is warm air at the top of the tower. In fact, because you're creating a greenhouse underneath, it actually turns out to be remarkably good for growing vegetation under there.

The Arizona Project

While this is not the first solar tower that has been built (a small-scale test rig in Spain proved the technology more than a decade ago) EnviroMission has chosen to build its first full-scale power plant in the deserts of Arizona, USA.

The Arizona tower will be a staggering 800 metres or so tall - just 30 meters shorter than the colossal Burj Khalifa in Dubai, the world's tallest man-made structure. To put that in context - it will stand more than double the height of the Empire State building in New York City, and it'll be as much as 130 meters in diameter at the top. Truly a gigantic structure.

Currently undergoing site-specific engineering and land acquisition, EnviroMission estimates the tower will cost around US$750 million to build. It will generate a peak of 200 megawatts, and run at an efficiency of around 60% - vastly more efficient and reliable than other renewable energy sources.

The output has already been pre-sold - the Southern California Public Power Authority recently signed a 30-year power purchase agreement with EnviroMission that will effectively allow the tower to provide enough energy for an estimated 150,000 US homes. Financial modelling projects that the tower will pay off its purchase price in just 11 years - and the engineering team are shooting for a structure that will stand for 80 years or more.

Considering that a large city like Los Angeles requires total power in the region of 7,200 megawatts, you'd have to build a few dozen solar towers up to the same size as the Arizona project if you wanted to completely replace the existing, primarily coal-based energy supply for that city's 3.7 million-odd residents. So it's not an instant solution - but then, its short projected payback period and virtually zero operating costs make it a very sound economic proposition that competes favorably against other renewable sources.

Under the terms of the pre-purchase agreement, the Arizona tower is due to begin delivering power at the start of 2015. Watch this space!

Cats do the Darnedest Things (20 pics)

Coconut Oil Isn't As Healthy As You Think It Is

There's no doubt coconut oil is having a moment — it's been touted as a cure-all for everything from heart disease to the inability to squeeze into your jeans after the holidays! But at 117 calories, 14g total fat and 12g saturated fat (60% of the daily value) per one tablespoon, there's reason to proceed with caution. Here, some of the most common claims we hear daily — debunked!

Claim #1: Coconut oil burns belly fat.

The Truth: No way, Jose. A few small-scale studies have linked downing extra-virgin coconut oil to decreased waist-circumference in individuals at risk for heart disease or diabetes, but mostly, participants had already started — and stayed — on a weight-loss diet before using coconut oil — which makes it difficult (not to mention, irresponsible!) to say that these results mean anything for the average Joe/Joanne like you and me. For now: Since plant-based oils of any kind are mostly made up of fat — using 1-2 tablespoons when cooking veggies, lean protein and/or whole-grains can help you stay full, making it easier to stick to any weight loss plan for the long-term.

Claim #2: Coconut oil revs metabolism.

The Truth: Again, in our dreams. The only truly dependable factor in changing your metabolic rate is to increase the ratio of lean body mass to free fat mass in your body (in other words: more muscles = increased metabolism). While some foods high in certain compounds such as caffeine may temporarily rev metabolism a teensy bit, coconut oil has yet to show any real results on that front. (And while we're on the topic of caffeine, bulletproof coffee — a.k.a. coffee and coconut oil — is also a weight-loss dead end. Remember, cream is a mostly saturated fat, just as coconut oil is, so the more you add, the more calories your cup o' joe contains.)

Claim #3: Coconut oil is anti-bacterial.

The Truth: About half of the fatty acids found in coconut oil are from a type of fatty acid called lauric acid, which has been linked to having antimicrobial, antifungal effects that may reduce risk of certain acute and chronic illnesses and diseases (e.g. a yeast infection vs. type 2 diabetes). But that's no reason to guzzle enough coconut oil to bathe your internal organs in the stuff! Research is still ongoing on the topic, but since you'd have to consume high amounts of the oil to truly reap the benefits of it. And since dietary fat from all plant-based oils can rack up quickly (thus contributing to weight gain over time), it may not be worth the risk.

Claim #4: Coconut oil is heart healthy.

The Truth: Nope. But it won't definitively increase your risk for heart disease, either. One tablespoon of coconut oil provides more than half the amount of saturated fat that the American Heart Association recommends per day! Foods that are high in saturated fat have been linked to been linked to increasing your total cholesterol in addition to your LDL (otherwise known as the "bad" cholesterol). In some studies, coconut oil helped to raise HDL (our "good" cholesterol) and total cholesterol — without necessarily affecting our LDL. But it's not enough to make a recommendation across the board. Since other heart-healthy oils, like soybean, hempseed, extra virgin olive oil or rapeseed, a.k.a. canola have been linked to lowering LDL and total cholesterol overall, these options are still better alternatives for those at risk for heart disease.

Claim #5: Coconut oil is good for cognition.

The Truth: Can coconut oil make your smarter? I wish — I'd have chugged it by the gallon in grad school! But where there is some promise is in developing research that supports the use of coconut oil in reducing risk of Alzheimer's disease progression in at-risk populations. That said, extra virgin olive oil (among others, such as corn oil) has also been linked to decreasing risk of dementia, cognitive decline and neurodegenerative diseases for the same reasons. Bottom line: Swap butter for plant-based oils that contain phytonutrients when you're cooking at home.

Claim #6: Coconut oil is helpful for diabetics.

The Truth: Any time a diabetic consumes a source of protein or fat in conjunction with carbohydrates, you slow down the rate at which glucose is absorbed from your gut and into your bloodstream — meaning that it'll stop your blood-sugar from spiking at the ready. Since coconut oil is a mostly saturated fat, diabetics may notice less of a sugar-spike when dousing any food in coconut oil … but that's by no means a blood sugar cure-all. In fact, since diets high in saturated fat are also linked to risk of diabetes, those who overload on the stuff may be putting themselves even more at risk for chronic disease. While some studies have linked coconut oil use to decreasing diabetes risk by enhancing insulin sensitivity, most of these have only been conducted in animal models.

Claim #7: Coconut oil is high-cholesterol.

The Truth: Despite the fact that you may see plant-based oils with labels that claim "no cholesterol" on packaging, there should never be dietary cholesterol in a plant-based oil — or food, for that matter! Cholesterol is a hormone that is made in the bodies of all animals (humans included! — which is why you won't (or shouldn't!) see it in vegetarian foods. That small fact aside, that doesn't stop food marketers from using it on labels — just know it's a-okay to ignore.

Claim #8: Coconut oil has a very high smoke point.

The Truth: At around 350°F, coconut oil has a relatively low smoke point as compared to other plant-based, antioxidant-packed oils such as corn, canola, grapeseed, sesame seed, avocado, peanut and soybean oils. While it's nutritionally similar to butter, it may be a better alternative to shortening for vegans or those who are severely lactose intolerant. Regardless, check labels on any plant-based oil that's solid at room temperature — that's a clear indicator of hydrogenation, which can have negative effects on your cholesterol and long-term heart health.

The Takeaway

While coconut oil can be delicious, choose it for its flavor profile, not for its perceived health benefits. All plant-based oils are great for you! And since they each have a "place" in your kitchen, all of 'em— when consumed regularly and in 1-2 tablespoons per day — can help you stay healthy and maintain weight for the long-term.

Got a craving? Here's what your body actually wants to eat

Ever find yourself rummaging through the fridge or kitchen cabinets for that delicious, satisfying something—except nothing seems to fill that void? Maybe you know what you’re craving, but would actually have to leave the house to go and buy it (who wants to do that?), or your craving is so ambiguous that even browsing the supermarket aisles might leave you stuck. Turns out, there’s more to your hankering than just hunger. “Often a food ‘search’ can arise when you’re in need of a break from work or sitting, so by nature you get up and stir around,” explains Lisa Cohn, RD, a New York City-based nutritionist. “Other times a quest can be triggered by an emotional or physical reaction that leaves us feeling frozen or out of control, and the act of searching for something to eat gives us a determination to take control.”

While there are several other potential reasons for sudden cravings, including a nutrient deficiency, sleep deprivation, and low blood sugar, there are healthy and satisfying snack choices you can make to quench a craving until your next meal. Here are nine expert-approved solutions and substitutes for every kind of craving.

If you’re craving carb-rich foods

When you crave carb-heavy eats like bread and pasta, it may be because your energy levels have taken a nosedive. Thing is, these same empty carbs can make you crave even more unhealthy foods. “When you go too long without eating, or consume too many simple carbohydrates, your blood sugar drops, triggering your body to reach for starchy foods that are quick and easily digestible,” explains Jessica "Chef Jess" Swift, RD, a Washington, DC-area nutritionist and classically trained chef. “This will allow your blood sugar to spike and get back to normal quickly, but not make you full.” If you’ve ever eaten pizza and then craved ice cream an hour later, this is what’s happening to your body.

If you’re craving carbs and nothing else will do, opt for whole grain—they're rich in fiber and take longer to digest, which means they'll keep you feeling full for longer than simple carbs. (Plus, there are plenty of other health benefits of whole grains.) This overnight oats recipe is a Health staff favorite.

If you’re craving something sweet

It’s easy to get a quick sugar fix from foods that might be lying around (hello, blueberry muffins in the office kitchenette). Chances are, though, that you're already eating way too much sugar; the average person takes in 22 teaspoons of sugar daily—more than three times the amount suggested by the American Heart Association. A growing body of research links the sweet stuff to high cholesterol and blood pressure, increased risk for cancer, diabetes, and heart disease, and—of course—excess weight gain. Plus, a sweet treat can cause a blood sugar spike and crash, leaving you feeling sluggish, moody, and hungry (again).

Reach for a piece of fruit instead. You'll be satisfied—we promise. “When you craving something cold, creamy and sweet, think healthier options like frozen bananas, grapes, organic fruit purees, or homemade frozen yogurt pops,” suggests Natalia Levey, certified health and nutrition coach and author of Cravings Boss. Low-fat Greek or plain yogurt with some fruit on top is another nutrient-packed option. “The yogurt provides calcium which is good for your bones and the berries are packed with immune boosting antioxidants,” says Keri Gans, RD, New York City-based nutritionist and author of The Small Change Diet.

If you’re craving something salty

“When you're overly stressed, your adrenal glands release cortisol, which can make you ravenous for high-fat, salty foods,” says Ashvini Mashru, RD, nutritionist and owner of Wellness Nutrition Concepts, LLC in Malvern, Penn. That's why stress often drives weight gain. But you can satisfy salty cravings without tacking tons of extra calories on to your day. Gans recommends roasting chickpeas tossed in heart-healthy olive oil and sprinkled with herbs and salt. “Chickpeas are a great choice when you don’t know what you want to eat because they’re a light snack, you can eat them on the go, and you can also experiment with different seasoning combos, depending on your mood,” says Gans. “And olive oil is a healthy fat that contains a monounsaturated, omega-9 fatty acid, important vitamins and antioxidants.”

 If you’re craving something hearty and filling

Pack a punch of pure protein to reduce hunger and keep future cravings at bay. “Because it takes more work and a longer time for your body to digest and breakdown protein, it will satisfy you for longer and keep hunger pangs at bay,” explains Mashru. It also helps promote lean body mass, which is essential for boosting your overall metabolic rate and healthy weight maintenance. Some leaner options include eggs, chicken, and turkey (you could also try this recipe for no-bake energy bites). “Eggs are a pure, high-quality protein that clock in at just 75 calories a pop,” says Gans. “I like to hard boil them and add a drop of salt and pepper when I don’t know exactly what I’m craving.”

If you’re craving something deep-fried

If you’ve had a low intake of fat for a few days your body can crave fatty things such as fried foods and butter. If you find yourself reaching for the crisps, try some nuts or avocado toast instead (here are four unique avocado toast recipes), as these foods are a far healthier way for you to get essential fats, says Chef Jess. Avocados are actually loaded with fat, which can help curb your craving for it, just not the type of fat you’re craving. “They’re rich in omega-3 fatty acids which are considered 'healthy fats' thanks to their heart- and brain-boosting benefits,” she explains. Nuts are also packed with omega-3s as well as vitamin B6, which is responsible for regulating hormones and fighting cravings. If you’re really looking to limit snacking in the midst of squashing your craving, opt for pistachios, which provide a barrier and visual cue of high volume with their shells.

If you’re craving something savory

A bowl of lentil soup can be a winner if you're craving a hot, savory dish. “Lentils are a good source of fiber and protein and this winning combination may help stabilize your blood sugars, keeping your appetite in check until your next meal,” says Gans. Another quick and easy sub? Sweet potatoes. Not only are they an excellent source of fiber, which means they take longer to digest, but they get your vision in check by providing over 400% of your daily vitamin A requirement in one medium-sized tater. If you’re stretched for time or don’t have access to an oven, simply pierce an uncooked sweet potato several times on each side and pop in the microwave for approximately 5 to 8 minutes, rotating halfway through.

If you’re craving something chocolatey

Most adults consume less than the recommended amount of dietary magnesium, which may explain why so many of us reach for magnesium-rich chocolate. “If you must, choose dark chocolate—about 75% cacao or higher,” says Mashru. “Additionally, eat foods high in magnesium, like nuts and seeds.” A great way to mix the two is to combine almonds, dark chocolate chips, and unsweetened coconut flakes together on a plate and pop it in the microwave, suggests Dawn Jackson Blatner, RDN, author of The Flexitarian Diet and The Superfood Swap. “The almonds will help you feel less munchy with their satisfying triple threat of protein, fat and fiber and the chocolate chips will hardly add calories when used sparingly.” Thirsty, yet craving something sweet? Pour yourself a glass of chocolate milk and reap the health benefits of dairy. Packed with nine essential nutrients, its benefits far outweigh the added sugar.

If you’re craving something salty and sweet

Can’t decide between the two tantalizing flavors but can’t think of one food item that satisfies both cravings? Grab some popcorn (try these 10 healthy flavored popcorn recipes). “I love popcorn because it is a 100% whole grain which is also heart healthy, and there are so many great ways to add flavor to it,” says Gans. Try adding some cinnamon and almond butter to air popped popcorn for the perfect balance of salty and sweet, as research shows the spice can reduce blood glucose levels, which can also help ward off cravings, and almond butter brings healthy fat that makes it taste extra decadent.

If you have no idea what you’re craving

Hydrate! Many times our bodies confuse thirst with hunger, the key reason it can be so difficult for us to decipher exactly what food item will satisfy the craving. “The same area of your brain that controls hunger also controls thirst, so sometimes signals get crossed when you haven’t had enough to drink during the day to confuse you into feeling the sensations of ‘hunger,’” explains Blatner. As it turns out, when your body is in need of water, it doesn’t particularly care if you get it from an actual glass of H2O or your favorite pint of Ben and Jerry’s. Your best bet is to drink a quick glass of water when cravings strike and then wait 15 minutes to see if you’re still craving something to eat.

7 Healthy Frozen Foods You Should Always Have on Hand

Eliminating processed foods from your diet is probably the best tip for keeping your weight in check and feeling fantastic. With such hectic schedules and a limited amount of time to spend in the kitchen, it’s also a pretty unrealistic goal. Thankfully, not all packaged goods are as devilish as you might expect.

When you think about it, any food that’s been altered from its original state is processed. That includes the cubed, fresh pineapple you often buy from the produce department as well as the pre-formed hamburger patties at the meat counter. Even the freezer aisle features tons of healthy foods that don’t contain much, if any, filler. The next time you’re stocking up, go for these seven frozen foods to speed your way to a healthy meal.

1. Shrimp

Most people’s freezers feature piles of raw chicken breasts and steaks, which are both great choices for assembling healthy and delicious meals. The problem with these large pieces of protein is you really have to plan in advance. If you don’t transfer the meat to your fridge to thaw out the night before, you’re in trouble because cooking from frozen takes significantly longer. In a pinch, you can thaw your protein in the microwave as per the guidelines from the USDA’s Food Safety and Inspection Service, but you’re bound to end up with dry, flavorless meat.

Frozen shrimp are a much better bet. These tiny crustaceans cook so fast from fresh, you’ll only add a minute or two to your prep time by adding them to your dish straight from the freezer. Shrimp are also a great source of lean protein. According to Men’s Health, you’ll score 18 grams of the muscle-building nutrient for just 84 calories when you eat a 3-ounce portion.

2. Brown rice

One of the most notable takeaways from the government’s updated dietary guidelines is the recommendation to increase our intake of whole grains since many of us are still scarfing a lot of refined carbs. Perhaps the easiest way to make this switch is by opting for brown rice instead of white varieties. The downside? Eating Well says brown rice can take up to 50 minutes to fully cook, while white rice typically falls in the 15- to 20-minute range.

You might be surprised to hear you can buy frozen, precooked brown rice right in your regular grocery store. It may take a bit of searching, though. You can add the grains straight to soups and stews, or steam in the microwave for a quick side.

3. Mixed berries

Antioxidant-rich berries are a favorite among health professionals. Though we’re a long way from knowing whether or not consuming the tiny fruits can aid in the fight against nasty diseases, preliminary research is looking good. One more recent review suggested consuming berries may reduce the risk of colon cancer.

While you can certainly purchase fresh, the frozen ones have a significantly longer shelf life and are often much less expensive. If you’re a smoothie or protein shake fan, they’re actually ideal since you’ll get a creamy, frosty texture without having to water down your drink by adding ice cubes.

4. Spinach

If you’re sick of having to wash, stem, and wilt greens every time you want to add them to a recipe, frozen spinach is a must. In fact, it may be even better for you than fresh leaves since it’s frozen very quickly after harvesting. Jeff Blumberg, a nutrition science professor at Tufts University, told The Washington Post fresh spinach can lose as much as half of its vitamin B content in a week.

For the best results, allow plenty of time for it to thaw, then wring out some of the excess moisture in a clean kitchen towel or several layers of paper towel before using. You can add the greens to everything from soups to casseroles to meatloaf.

5. Precooked meatballs

Frozen meatballs can be a great choice, but they can also be a terrible one if you aren’t careful. Many are loaded with preservatives and are more soy than actual meat, so be sure to check out the ingredient list before adding them to your cart. For a rundown of the best and worst choices based on ingredients as well as taste, check out this lineup from The Mercury News.

6. Peas

Like spinach, peas are another great vegetable option in the freezer aisle. In 2014, an in-depth study in the Journal of Agriculture and Food Chemistry reported on the nutrient retention of frozen versus fresh fruits and vegetables. The results for peas were particularly interesting because they demonstrated the frozen version actually retains higher levels of certain vitamins than fresh peas.

Because they thaw so fast, peas can almost always go straight from the freezer into whatever you’re cooking. Cold preparations are an exception, but you can still thaw the veggies super fast by dunking them in simmering water, then draining after a minute or two.

7. Quality frozen pizza

Yes, frozen pizza can be healthy. Today’s options are a lot more varied than what you remember from childhood, so take a little bit of time to study your options because the range in quality is huge. Go for ones that keep ingredients to a minimum and stay within a reasonable calorie range. Head over to Eat This, Not That! to take a look at some great choices.