Rooftop Solar and EVs Save Water and Cut Pollution: Better Use of Data Will Optimize the Benefits
By Beia Spiller
Thanks to improvements in technology, it's easier than ever to be green.
Solar panels and electric vehicles (EVs) are two prime examples of technologies that can help people minimize their environmental footprint, without sacrificing comfort or having to radically change their daily behavior. But the question still remains: How much of an environmental benefit do these technologies actually produce? And, are there actions that owners of these technologies can take to minimize their pollution footprint even more?
A new paper by my colleagues and me, recently published in Energy Economics, attempts to answer these two questions for households in Austin, Texas. These homes are part of Pecan Street Inc., a living smart-grid laboratory with the largest customer energy-use database on the planet. Using detailed household-level data from 2013-2015, we were able to track solar panel performance and EV use and charging patterns, and match these actions to two important environmental impacts: water use and greenhouse gas (GHG) emissions.
Our paper confirms that, in Texas, using residential solar panels consumes less water and pollutes the air less than using the central-grid power (based on its electricity sources during those years), and driving an EV instead of a gasoline vehicle generally reduces the household's water and emission footprint, even though EVs charge from the grid. Moreover, our analysis demonstrates how carefully examining energy-use data can help us make sure we're maximizing clean energy's benefits.
People may know that burning fossil fuels—whether to create electricity or drive gasoline vehicles—emits gases that pollute the air. But you may ask, how do the central electric grid and cars use water?
Water is used to produce many forms of energy, including both fossil-fuel based electricity and gasoline. For electricity generation in a natural gas or coal plant, large quantities of water are used for process-related needs, as well as to cool the power plant. The production and refinement of gasoline also uses a lot of water; in fact, we calculate that it takes about four gallons of water to produce one gallon of gasoline.
Wind and solar PV, on the other hand, need virtually no water to create power, and they do not emit GHGs or other pollutants in the process.
The solar findings
Because solar panels consume no water and emit no pollution, installing a solar panel allows a household to reduce both the water use and air pollution associated with grid electricity.
In fact, we find that solar panels in Texas have a very large and positive impact on both water and GHG emissions, reducing a household's combined footprint by about 75 percent (a previous Pecan Street study also found solar panels reduce homes' water-intensity by approximately 79 percent).
In Texas during the day when the sun shines, the main power sources are natural gas and coal. So, if you're getting some or all of your power from your own solar panels, you're avoiding using that high-GHG emitting, thirsty electricity from the grid.
Importantly, we find that a household can improve its environmental footprint even further by facing its solar panels south, capturing more sun throughout the day. However, this can conflict with local electric system attempts to maximize production during periods of peak demand, generally in the afternoon when people are getting home from school and work. For example, Pecan Street provided subsidies for solar owners in their community who face their panels west, thereby generating more electricity during that afternoon period, but less overall over the course of the day. Less electricity from the solar panels overall means more water use and emissions from the central grid.
This contradiction highlights the importance of analyzing data. A better understanding of hourly energy usage and emissions can inform electric system policies and pricing that lead to a reduction in total costs, including those related to the environment.
The EV findings
Understanding electric vehicles' environmental impact by these measurements is a bit trickier, because EVs avoid gasoline (thereby reducing water use and GHGs), but they also charge using the grid, which in Texas is largely powered by fossil fuels (thereby increasing both water use and GHG emissions).
Our paper therefore tested whether, on net, EVs are good for the environment—in this case by reducing water use and GHGs—in Texas.
To be able to quantify the environmental benefits of EVs, we needed to think about what vehicle the household would have driven had it not purchased an EV. Vehicle owners have many choices in the marketplace, and fuel efficiency is not the only deciding factor. For example, a family with many children or someone who needs to haul a trailer may not be willing to trade off vehicle size or horsepower in favor of a more compact EV. On the other hand, a person who likes small cars may place greater weight on fuel efficiency; this person's alternative to an EV is more likely to be a hybrid, whereas the large family's alternative vehicle is more likely to be a minivan.
Understanding what the alternative choice would have been is key in measuring the environmental impact of an EV: the less fuel-efficient the alternative vehicle, the better the EV is for the environment. For example, if you switch from driving a gas-guzzler to an EV, that's more beneficial than someone switching from a hybrid. In fact, we find that if the household's alternative-choice vehicle is a hybrid, using an EV can actually increase its net water use—the reduction in gasoline use is very small due to the high efficiency of the hybrid, and the EV is charged with thirsty grid electricity.
That said, we find that EVs always reduce GHG emissions, on net, regardless of the alternative vehicle. Although the benefits do vary largely with the efficiency of the alternative vehicle, they would always increase the cleaner the grid becomes.
Our findings related to EVs suggest three distinct policy solutions:
- Ensure that vehicles such as SUVs and trucks have electric offerings, which manufacturers like Tesla and Volvo are already working on. This will help steer those who require larger sized vehicles towards choosing an electric option, thereby drastically reducing their environmental footprint.
- When people purchase a new EV, a well-designed rebate program that pays them to surrender their inefficient vehicle to be destroyed (such as an improved "Cash-for-Clunkers" program from 2009) could lead to even greater reductions in the environmental impacts of driving.
- Ensure more grid electricity comes from solar and wind, thereby further improving the water- and emission-intensity of EVs. Especially as EV adoption increases, having a clean grid will help us achieve a more environmentally-friendly transportation sector.
Solar panels and electric vehicles will help pave the way to a cleaner future, but we must dig into the details to ensure we maximize the environmental benefits. The more data we have and examine, the better that decision-makers can design energy programs and incentives to improve our environmental footprint.
A Yellowstone National Park trail camera received a surprising visitor last month.
- Road to Nowhere: Highways Pose Existential Threat to Wolverines ... ›
- Court Ends Attempt to Mine for Gold Near Yellowstone - EcoWatch ›
EcoWatch Daily Newsletter
For the first time, researchers have identified 100 transnational corporations that take home the majority of profits from the ocean's economy.
- 3 Innovations Leading the Fight to Save Our Ocean - EcoWatch ›
- 5 Ways to Curb the Power of Corporations and Billionaires - EcoWatch ›
Environmental groups and the foundations that fund them made incremental, if mixed, progress toward diversifying their staff and leadership in 2020 but remain overwhelmingly white, according to a report issued by Green 2.0 Wednesday.
- 15 EcoWatch Stories on Environmental and Racial Injustice ... ›
- A Look at Why Environmentalism Is So Homogeneous — and How ... ›
- The Power of Inclusive, Intergenerational Climate Activism - EcoWatch ›
- Decolonizing Environmentalism - EcoWatch ›
By Jill Joyce
Maybe you're trying to eat healthier these days, aiming to get enough of the good stuff and limit the less-good stuff. You're paying attention to things like fiber and fat and vitamins … and anti-nutrients?
What Are Anti-Nutrients?<p><a href="https://www.hsph.harvard.edu/nutritionsource/anti-nutrients/" target="_blank" rel="noopener noreferrer">Anti-nutrients are substances</a> that naturally occur in plant and animal foods.</p><p>The name comes from how they function in your body once you eat them. They <a href="https://www.sciencedirect.com/topics/food-science/antinutrients" target="_blank">block or interfere with how your body</a> <a href="https://doi.org/10.1631/jzus.B0710640" target="_blank" rel="noopener noreferrer">absorbs other nutrients</a> out of your gut and into your bloodstream so you can then use them. Thus, anti-nutrients may decrease the amount of nutrients you actually get from your food. They most commonly interfere with the absorption of <a href="https://doi.org/10.1016/j.jand.2016.09.025" target="_blank" rel="noopener noreferrer">calcium, iron, potassium, magnesium and zinc</a>.</p><p>Plants evolved these <a href="https://www.todaysdietitian.com/newarchives/070111p54.shtml" target="_blank" rel="noopener noreferrer">compounds as a defensive mechanism</a> against insects, parasites, bacteria and fungi. For example, some anti-nutrients can cause a food to taste bitter; animals won't want to eat it, leaving the seed, for instance, to provide nourishment for future seedlings. Some anti-nutrients block the digestion of seeds that are eaten. The seeds disperse when they come out the other end in the animal's fecal matter and can go on to grow new plants. Both of these survival tactics help the plant species grow and spread.</p><p><span></span>In terms of foods that people eat, you'll most commonly find anti-nutrients naturally occurring in whole grains and legumes.</p>
Time for an Image Makeover as Health Enhancers<p>Despite sounding scary, studies show that anti-nutrients are not of concern unless consumed in <a href="https://doi.org/10.1016/j.jcs.2014.01.010" target="_blank">ultra, unrealistically high amounts</a> – and they have numerous health benefits.</p><p>Anti-nutrients are currently undergoing a change in image very similar to the one dietary fiber experienced. At one point, scientists thought dietary fiber was bad for people. Since fiber could bind to nutrients and pull them out of the digestive tract in poop, it seemed like something to avoid. To address this perceived issue, grain processing in the late 1800s removed fiber from foods.</p><p>But now scientists know that <a href="https://doi.org/10.1111/j.1753-4887.2009.00189.x" target="_blank">dietary fiber is incredibly important</a> and encourage its consumption. Eating plenty of fiber lowers the risks of obesity, high blood pressure, heart disease, stroke, diabetes and some gastrointestinal diseases.</p><p>In the same way, rather than something to avoid, many anti-nutrients are now considered health-promoting nutraceuticals and functional foods due to their numerous benefits. Here's an introduction to some of the most frequently eaten anti-nutrients that come with benefits:</p><ul><li><a href="https://doi.org/10.1089/109662004322984734" target="_blank" rel="noopener noreferrer">Saponins, common in legumes</a>, can boost the immune system, reduce risk of cancer, lower cholesterol, lower blood sugar response to foods, result in fewer cavities, reduce risk of kidney stones and combat blood clotting seen in heart attacks and strokes.</li><li><a href="https://doi.org/10.1016/j.jcs.2014.01.010" target="_blank" rel="noopener noreferrer">Lectins, found in cereal grains and legumes</a>, are associated with reduced risk of cardiovascular disease, diabetes, some cancers and becoming overweight or obese.</li><li><a href="https://doi.org/10.1080/10408699891274273" target="_blank" rel="noopener noreferrer">Tannins, commonly found in teas, coffees and processed meats and cheeses</a>, are antioxidants that can inhibit growth of bacteria, viruses, fungi and yeast and may decrease cholesterol levels and blood pressure.</li><li><a href="https://doi.org/10.1631/jzus.B0710640" target="_blank" rel="noopener noreferrer">Phytates, found in wheat, barley, rice and corn</a>, are associated with increased immune function and cancer cell death, as well as reduced cancer cell growth and spread. They also have antioxidant properties and can reduce inflammation.</li><li>Finally, <a href="https://doi.org/10.1024/0300-98188.8.131.52" target="_blank" rel="noopener noreferrer">glucosinates, found in brassica vegetables</a> like cauliflower, inhibit tumor cell growth.</li></ul><p>Oxalates are one of the few anti-nutrients with mostly negative impacts on the body. They are <a href="https://www.uofmhealth.org/health-library/aa166321" target="_blank" rel="noopener noreferrer">found in lots of common foods</a>, including legumes, beets, berries, cranberries, oranges, chocolate, tofu, wheat bran, soda, coffee, tea, beer, dark green vegetables and sweet potatoes. The negative impacts of oxalates include binding to calcium in the digestive tract and removing it from the body in bowel movements. Oxalates can also <a href="https://www.uofmhealth.org/health-library/aa166321" target="_blank" rel="noopener noreferrer">increase the risk of kidney stones</a> in some people.</p>
Fitting Anti-Nutrients Into a Healthy Diet<p>Overall, comparing the benefits to the drawbacks, anti-nutrient pros actually outweigh the cons. The healthy foods that contain them – mainly fruits, vegetables, whole grains and legumes – should be encouraged not avoided.</p><p>Anti-nutrients become a concern only if these foods are consumed in ultra-high amounts, <a href="https://www.ars.usda.gov/research/project/?accnNo=426312" target="_blank" rel="noopener noreferrer">which is very unlikely</a> for most adults and children in the U.S. Additionally, a large proportion of anti-nutrients are removed or lost from foods people eat <a href="https://www.hsph.harvard.edu/nutritionsource/anti-nutrients/" target="_blank" rel="noopener noreferrer">as they're processed and cooked</a>, especially if soaking, blanching, boiling or other high-heat processes are involved.</p><p>Vegetarians and vegans may be at higher risk of negative effects from anti-nutrients because their diet relies heavily on fruits, vegetables, whole grains and legumes. But these <a href="https://doi.org/10.1016/j.jand.2016.09.025" target="_blank" rel="noopener noreferrer">plant-based diets are still among the healthiest</a> and are associated with reduced risk of cardiovascular disease, obesity, diabetes and numerous types of cancers.</p><p>Vegetarians and vegans can take a few steps to help counteract anti-nutrients' effects on their absorption of particular nutrients:</p><ul><li>Pair high iron <a href="https://doi.org/10.1093/jn/130.5.1378S" target="_blank" rel="noopener noreferrer">and zinc</a> <a href="https://doi.org/10.1016/bs.afnr.2014.11.003" target="_blank" rel="noopener noreferrer">foods with</a> <a href="https://doi.org/10.1093/ajcn/59.5.1233S" target="_blank" rel="noopener noreferrer">foods high in vitamin C</a> (examples: meatballs with tomato sauce, tomato-based chili with beans).</li><li><a href="https://www.jblearning.com/catalog/productdetails/9780763779764?jblsearch" target="_blank" rel="noopener noreferrer">Soak legumes before cooking</a>.</li><li><a href="https://doi.org/10.1093/ajcn/70.3.543s" target="_blank" rel="noopener noreferrer">Time dairy intake</a> such that it is not always paired with high oxalate foods.</li><li>Purchase dairy products that are fortified with calcium.</li><li>Consider a multivitamin-mineral supplement with about 100% of the daily recommended dose of nutrients (check the nutrition facts panel) as nutrition insurance if you are worried, but be sure to talk to your doctor first.<em></em></li></ul><p><em><a href="https://theconversation.com/profiles/jill-joyce-1172925" target="_blank" rel="noopener noreferrer">Jill Joyce</a> is an assistant professor of Public Health Nutrition at Oklahoma State University.</em></p><p><em>Disclosure statement: Jill Joyce does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</em></p><p><em>Reposted with permission from <a href="https://theconversation.com/anti-nutrients-theyre-part-of-a-normal-diet-and-not-as-scary-as-they-sound-149229" target="_blank" rel="noopener noreferrer">The Conversation</a>.</em></p>
- Good Nutrition Can Help Keep COVID-19 and Other Diseases Away ... ›
- Vitamin K: A Little-Known But Noteworthy Nutrient - EcoWatch ›
Toxins enter the body through what we eat, drink, breathe in, and process in any way. Once inside, toxins overtax our immune system and detoxification system and leave us more vulnerable to illness — not ideal during cold and flu season, and especially not this year during a pandemic — and make us age a little faster, too.
1. Source Your Food Wisely<p>Try to stay away from packaged and processed foods that contain ingredients you can't pronounce, and instead reach for fresh food from natural sources. Aim to make vegetables more than 50% of your daily diet — their fiber is a great natural binder, and they're full of beneficial <a href="https://vitalplan.com/blog/the-case-of-the-missing-phytochemicals-and-how-to-get-them-back" target="_blank" rel="noopener noreferrer" style="">phytochemicals</a> — and minimize your red meat consumption.</p><p>Also, whenever practical, choose <a href="https://vitalplan.com/blog/how-to-eat-organic-without-spending-a-fortune" target="_blank" rel="noopener noreferrer">organic</a> over conventional products. That said, we know organic prices and accessibility can be an issue, so for help making strategic decisions, refer to the <a href="https://www.ewg.org/" target="_blank" rel="noopener noreferrer">Environmental Working Group</a> (EWG) "Dirty Dozen" and "Clean Fifteen" lists:</p><h3>The Dirty Dozen:</h3><ol><li>Strawberries</li><li>Spinach</li><li>Kale</li><li>Nectarines</li><li>Apples</li><li>Grapes</li><li>Peaches</li><li>Cherries</li><li>Pears</li><li>Tomatoes</li><li>Celery</li><li>Potatoes</li><li>Raisins*</li></ol><p><em>(*While raisins aren't technically a fresh food, the EWG found that they are "one of the dirtiest produce commodities on the market — and even some organic raisins are contaminated.")</em></p><h3>The Clean Fifteen</h3><ol><li>Avocado</li><li>Sweet corn</li><li>Pineapple</li><li>Onion</li><li>Papaya</li><li>Frozen sweet peas</li><li>Eggplant</li><li>Asparagus</li><li>Cauliflower</li><li>Cantaloupe</li><li>Broccoli</li><li>Mushrooms</li><li>Cabbage</li><li>Honeydew</li><li>Kiwi</li></ol>
2. Consider Detoxifying and Immune-Boosting Herbs<p>There are a number of herbs and natural ingredients that can help support detoxification and immune health. Here are the ones at the top of Dr. Rawls' list:</p><p><span></span><strong>Chlorella:</strong> This nutrient-rich freshwater algae binds to toxins so they can be eliminated from your body more efficiently. Chlorella works particularly well for withdrawing heavy metals. Pure chlorella can be purchased in the form of bulk powder, tablets, or capsules.</p><p><strong><a href="https://vitalplan.com/ingredients/milk-thistle" target="_blank">Milk Thistle</a>:</strong> It's been used for thousands of years to support a healthy liver, the primary organ responsible for detoxification.</p><p><strong>Dandelion:</strong> Known to help support liver function, research suggests <a href="https://vitalplan.com/ingredients/dandelion-extract" target="_blank">dandelion</a> helps promote the body's natural detoxification and elimination processes.</p><p><strong>Bitters:</strong> <a href="https://vitalplan.com/blog/the-impressive-health-benefits-of-bitter-foods" target="_blank">Bitter</a> flavors are important to digestion — they stimulate the release of the saliva, enzymes, and bile that help break down your food. Include bitter herbs and foods in each meal, or take a botanical extract that blends bitter herbs like dandelion root, burdock root, orange peel, and gentian root</p><p><strong>Reishi mushroom:</strong> An extensively studied adaptogenic mushroom, <a href="https://vitalplan.com/ingredients/reishi" target="_blank">reishi</a> has exceptional immunomodulating and antiviral properties. It helps normalize <a href="https://vitalplan.com/blog/are-you-inflammaging-how-to-stop-the-inflammation-that-speeds-up-aging" target="_blank">inflammatory</a> cytokines and promotes healthy immune response against threatening <a href="https://vitalplan.com/blog/the-immortal-life-of-your-microbiome" target="_blank" rel="noopener noreferrer">microbes</a>.</p><p><strong>Rhodiola:</strong> Another adaptogen, <a href="https://vitalplan.com/ingredients/rhodiola" target="_blank">rhodiola</a> improves stress tolerance by reducing fatigue, supporting energy levels, and improving tissue oxygenation.</p><p><span></span><strong><a href="https://vitalplan.com/ingredients/turmeric" target="_blank">Turmeric</a>:</strong> This popular spice is well loved for its anti-inflammatory and antioxidant properties.</p><p><strong>Shilajit:</strong> An herbo-mineral adaptogen, <a href="https://vitalplan.com/ingredients/shilajit" target="_blank">shilajit</a> has a long history of use in traditional Indian medicine for longevity and strength. It's also an immunomodulator with antioxidant, anti-inflammatory, and antiviral properties.</p><p><strong>Gotu Kola:</strong> Best known for improving memory and mood, <a href="https://vitalplan.com/ingredients/gotu-kola" target="_blank">gotu kola</a> is also great for promoting a normal response to inflammation, balancing stress hormones, and supporting circulation.</p>
3. Filter Your Water<p>Much of America's tap water has been shown to contain pollutants, so filtering what comes out of your kitchen sink is smart. To be sure you're using a filter that does the trick, keep these guidelines in mind:</p><ul><li>Look for a filter certified by NSF International or the Water Quality Association.</li><li>Choose one that removes the contaminants in your water (check your local drinking water quality report to see what's present).</li><li>Change your water filters on time.</li></ul>
4. Choose Safe and Effective Cleaning Supplies<p>When buying household cleaning products, don't bring home chemicals that could harm your health more than some of the microbes you're trying to get rid of. Fortunately, there are a number of products on the market that work safely; here are some ways to shop wisely:</p><ul><li>Look for the Green Seal, Ecologo, or Safer Choice (EPA) seals.</li><li>Opt for fragrance-free options.</li><li>Avoid triclosan and quaternary ammonium compounds or "quats." (One tactic is to choose products that don't advertise as "antibacterial.")</li><li>Consult the EWG's list of <a href="https://www.ewg.org/news-and-analysis/2020/03/16-effective-and-safe-products-guard-against-coronavirus" target="_blank" rel="noopener noreferrer">safe and effective products</a> for guarding against coronavirus.</li></ul>
5. Opt for Non-Toxic Beauty and Personal Care Products<p>There are a lot of claims made on beauty and self-care products these days, but words alone, like "natural," "organic," "non-toxic," "clean," "green," and "eco-friendly," don't mean a thing — they aren't backed by any sort of regulatory or certification processes. Instead, to find non-toxic products you trust, you have to do a little research.</p><p>Start by checking reputable ratings databases like <a href="https://www.ewg.org/skindeep/" target="_blank" rel="noopener noreferrer">Skin Deep</a> (EWG) and <a href="https://www.thinkdirtyapp.com/" target="_blank" rel="noopener noreferrer">Think Dirty</a>. Another good bet: Look for reliable third-party certifications on products labels, including:</p><ul><li>USDA Organic</li><li>EWG Verified</li><li>Made Safe</li><li>NSF/ANSI 305</li><li>Natural Products Association Certified</li><li>Whole Foods Market Premium Body Care</li></ul>
6. Get Outside<p>One more reason to <a href="https://vitalplan.com/blog/how-to-feel-great-and-boost-longevity-in-just-17-minutes-a-day" target="_blank" rel="noopener noreferrer" style="">get outdoors</a> beyond combatting cabin fever: The air in natural environments is generally much cleaner than indoor air. For one, outdoor air contains ⅔ less carbon dioxide, high levels of which negatively affect our productivity, <a href="https://vitalplan.com/blog/natural-sleep-aids" target="_blank" rel="noopener noreferrer" style="">sleep</a>, and more.</p><p>Forest air in particular contains phytoncides, organic compounds emitted by trees and plants that have been shown to boost our immune system function, plus plants in general help neutralize toxic substances in the air. Forests, open spaces, and open water are also rich in negative ions, which reduce inflammation.</p><p>So take your pick of natural environs, and get out there as often as possible — while still maintaining at least 6 feet of distance between yourself and others, of course.</p>
7. Bring Nature Indoors<p>Plants are natural air purifiers, so bringing some plants indoors can help clear the air in your home. Here's a list of the top 10 air-purifying plants to consider:</p><ul><li>Areca palm</li><li>Lady palm</li><li>Bamboo palm</li><li>Rubber plant</li><li>Dracaena</li><li>English ivy</li><li>Dwarf date palm</li><li>Ficus</li><li>Boston fern</li><li>Peace lily</li></ul>
8. Drive Less, Move More<p>Staying off the roads decreases air pollution, and the fact that many of us are driving less these days is noticeably improving air quality. If your commute is on hold, try to translate some of your usual travel time into getting more physical activity, or sneak in more movement between other normal routines.</p><p>Exercise improves circulation, oxygenates your tissues, and enhances the work of the lymphatic system through muscle contractions — all of which make it easier to move toxins out of your body.</p>
9. Practice Forgiveness<p>Through the practice of gratitude, we stay centered and in the present moment. This allows us to move through situations from our heart. Take time to forgive someone or yourself for things in the past. When we forgive, we expand and open up to endless possibilities.</p>
10. Quit a Bad Habit<p>Are you a smoker? Pack rat? Chronically sleep-deprived? In a bad relationship? Toxins come into our lives in many forms. Consider if you're participating in any unhealthy patterns or holding onto anything that no longer serves you, and then find a way to limit those things in your life.</p>
- 15 Supplements to Boost Your Immune System Right Now - EcoWatch ›
- The Immune System's Fight Against the Coronavirus - EcoWatch ›