We always advise speaking with at least a few certified solar installers to understand how all the factors will affect your output. Solar panels indicate how much power they intend to produce under ideal conditions, otherwise known as the maximum power rating. But how much electricity your solar panels produce depends on several factors. Because the seasons and weather conditions affect the amount of sunlight hitting your roof, and the amount of sunlight also varies on the time day, you can’t use just the max power rating to predict how much power you’ll get. However, your location will allow you to do some math and determine how well a solar panel works where you are. A kilowatt-hour is a basic unit of energy, which is equal to power (1000 watts) times time (hour). Your electric bills show how the average number of kWh you use per month. For example, a 50 Watt light bulb left on for one hour would be 50 Watt hours, and 20 50 watt light bulbs running for one hour would be 1 kilowatt-hour (kWh). 

According to the U.S. Energy Information Administration, the average monthly electricity consumption for a residential utility customer is about 903 kWh per month. Divide your average monthly usage by 30 days in a month to get your daily usage. If you’re going by the national average, then you should be using about 30 kWh per day. Next, figure out the average amount of sunlight you get per day. The US ranges from about 4 hours – 6 hours of sunlight per day, on average, see the below map. where to sell used ac unitLet’s estimate you get about five hours per day to generate that 30 kWh you use. what are the different brands of ac unitsSo the kWh divided by the hours of sun equals the kW needed. ac/dc power supply manufacturers

Or, 30 kWh / 5 hours of sun = 6 kW of AC output needed to cover 100% of your energy usage. Typically, a modern solar panel produces between 250 to 270 watts of peak power (e.g. 250Wp DC) in controlled conditions. This is called the ‘nameplate rating’ This varies based on the size and efficiency of your panel. There are plenty of solar calculators, and the brand of solar system you choose probably offers one. That said, there is a simple equation to calculate the amount of kilowatt-hours (kWh) your solar panel system will produce. So now that we know you need to produce about 6kW of AC output, we can work backwards to figure out how many solar panels you need. Solar panels produce direct current (DC), and your home runs on alternating current (AC). Yep, like the band, AC/DC. Because of physics, there are losses in converting the energy from the sun into DC power, and turning the DC power into AC power. This ratio of AC to DC is called the ‘derate factor’, and is typically about .8.

This means you convert about 80% of the DC power into AC power. This continues to improve ever so slightly, but the losses are unavoidable… because of physics! So you take the AC amount you need: 6kW and divide by .8 (6kW/.8 = 7.5kW DC). This means that you’ll need 30 250Wp solar panels or 27-28 270Wp panels. Finally, let’s find out how much you can save per month on average from your monthly electric bill! Let’s plug it all in: On average, your solar system is going to lose some energy due to wiring, power, inverter efficiency, so you actually end up using 80% of your solar system’s capacity. To figure out how many kilowatt-hours (kWh) your solar panel system puts out per year, you need to multiply the size of your system in kW DC times the .8 derate factor times the number of hours of sun. So if you have a 7.5 kW DC system working an average of 5 hours per day, 365 days a year, it’ll result in 10,950 kWh in a year. If you divide your expected 10,950 kWh of annual production by 12, you’ll see that your system will offset about 912 kWh per month from your monthly electric bill, which can translate to $100 or more (in California this would save you about $250) per month depending on how much you pay per kWh!

So to break this down into simple math that you can do: AC rating = Average kWh per month / 30 days / average sun hours per day example: 903 kWh per month / 30 days / 5 hours = 6.02 kW AC DC rating = AC rating / derate factor (.8 is conservative, but a range would be .8 – .85) example: 6.02 kW AC / .8 = 7.53 kW DC Number of panels = DC rating / Panel Rating (e.g. 25o W) *note this is important b/c panels are rated in watts, and the systems are rated in kilowatts (1000 watts). So a 7.53 kW system = 7530 Watts and a 250 watt panel = .250 kW example: 7.53 kW x 1000 / 250 watt = 30.12 panels, so roughly 30 250 panels (30 x 250W = 7500 Watts = 7.5 kW) NOTE: to get your average usage, preferably add up your last 12 months usage and divide by 12. In a pinch, the last 6 months can be a close approximation, but a year’s worth of data is far better. Have you calculated how much your solar system will produce? Tell us in the comments! Image Credit: via FlickR under a Creative Commons license, By NREL [Public domain], via Wikimedia Commons

Electricity usage is calculated in kilowatt-hours. A kilowatt-hour is 1,000 watts used for one hour. As an example, a 100-watt light bulb operating for ten hours would use one kilowatt-hour. How to calculate electric usage cost: 1. Volts x Amps = Watts 2. Watts ÷ 1,000 = Kilowatts (kW) 3. Kilowatts (kW) x Hours of Use = Kilowatt Hours (kWh) 4. Kilowatt Hours (kWh) x kWh rate = Cost of Usage 5. Add TVA Power Cost Adjustment charge per kWh Below are some examples of electrical appliances found in most homes. These examples are using a 10 cents per kWh rate. For other tips on saving energy visit the Department of Energy Web site, Energy Savers – Tips on Saving Energy and Money at HomeThe page you are looking for might have been removed, had its name changed, or is temporarily unavailable. Please click here to go back to the home page.The Dominican Republic is an island nation in the Caribbean situated between Cuba and Puerto Rico. The country's 18,700 square miles of territory extends over more than half of the island it shares with Haiti.

It is home to a diverse natural landscape that includes white-sand beaches, fertile plains and breathtaking mountain ranges that reach elevations over 10,000 feet, the highest in the region. The Dominican Republic is also home to a growing population of expatriates, who live in cities throughout the country. While the Dominican Republic is not the cheapest retirement destination in the world, it does provide excellent value for money compared to most other destinations in the Caribbean. It is absolutely possible to live comfortably in the country on a $1,000 monthly budget. Most single expatriates living alone would probably benefit from a slightly higher budget of around $1,200 per month. However, if you're sharing housing costs with a spouse or roommate, a $1,000 monthly budget per person should be enough to live very comfortably. Comfortable and affordable housing is available around the country. The capital, Santo Domingo, delivers a fast-paced urban lifestyle with easy access to services, health care, cultural attractions, shopping and everything else a modern city provides.

Popular coastal cities include Puerto Plata, Sosúa and Cabrera in the north, and Samana and Punta Cana in the east. Many expatriates prefer to get away from heavily touristed areas by settling in smaller towns dotting the coastline. Inland destinations include the bustling city of Santiago de los Caballeros near the north coast and the cooler highland cities of Jarabacoa and Constanza, which are located in the center of the country at 1,700 and 3,800 feet of elevation, respectively. While inexpensive housing is available across the country, rents tend to spike in tourist centers. That said, prices are almost always much more reasonable in surrounding neighborhoods, so spend some time searching for a better deal nearby. Careful apartment hunting can have a big impact on your monthly expenses. A one-bedroom apartment in the central districts of Santo Domingo costs around $415 per month. This is probably the upper limit on rent that allows you to maintain a good living standard on a $1,000 monthly budget.

To save some money, seek out better deals available in outlying neighborhoods. The average price for a nice one-bedroom apartment outside the central districts of Santo Domingo is about $250 per month, while a three-bedroom unit goes for a little over $510 on average. For inexpensive coastal living, Puerto Plata and nearby towns are very good options. A one-bedroom apartment in the center of Puerto Plata is about $270 per month, while the average price for a three-bedroom condominium is only about $405. Prices fall by $100 or more for similar accommodations outside the center. Punta Cana, at the southern tip of the island, is more expensive. Rent in a centrally located one-bedroom apartment is around $440. Outside the center, similar accommodation is about $330, while a three-bedroom unit goes for around $415. The national average for utilities, including electricity, water and garbage service, is about $62. This is based on moderate electricity use, so budget more if you expect to make regular use of the air conditioner.

As of 2015, electricity outages are somewhat common in the Dominican Republic. Some expatriates invest in gas-powered generators to provide power during outages. Unlimited broadband Internet service costs about $50 per month across the country. Prepaid cellphone service costs about 17 cents per minute on average, not including plan-based discounts or promotional deals. Locally produced food in grocery stores and markets is generally inexpensive in the Dominican Republic. Familiar staple foods such as rice, eggs, corn, beans, potatoes and chicken feature prominently in local cuisine and are cheap across the country. The average price of a loaf of bread is about $1.25, rice is 60 cents per pound, a dozen eggs costs about $1.60 and boneless, skinless chicken breast costs about $2.65 per pound. As a relatively small island nation, the Dominican Republic imports many of the consumer packaged goods on its shelves. All kinds of international food products, including cheeses, meats, beer and chocolate, are available in cities and tourist centers.

Imported food is generally quite expensive, so stick to local-brand products whenever available. By shopping outside tourist centers, choosing locally produced foods and cooking at home, you can enjoy a varied, exciting diet on $200 or less without much trouble. On a $1,000 budget, there's not a lot of room for regular restaurant dining in the Dominican Republic. A cheap, tasty meal in a busy neighborhood restaurant costs about $5 to $7 in many cities. Expect to pay nearly $35 for a three-course meal for two people at a mid-range restaurant, not including alcoholic drinks. For a cheaper option, delicious meals are often available for under $3 from neighborhood food carts. Health care in the Dominican Republic is generally much less expensive than in the United States. However, first-rate care is limited to private hospitals in bigger cities such as Santo Domingo and Santiago de los Caballeros. Private clinics offering high-quality care are available in many of the popular expatriate and tourist centers, but they do not provide the full range of medical services typically found in hospitals.

Expatriates generally avoid the publicly operated hospitals and clinics located around the country. While doctor visits and other health care services are generally very cheap in the Dominican Republic, most expatriates carry health insurance while living in the country. Monthly policy premiums range between $30 and $100 per month, and policies are available from domestic and international insurers. Household cleaning items, personal hygiene products and other common goods are generally inexpensive in the Dominican Republic. However, imported products, such as deodorant and contact lens solution, for example, range closer to U.S. prices. Most expatriates can meet a budget of about $100 per month in this category. If you regularly purchase cosmetics, contact lenses, clothes and other products, you may need a bigger budget in this area. The Dominican Republic's larger cities have public bus systems, while most cities rely on a mix of other options. Passenger cars, vans and trucks, known as públicos, follow set routes in many cities.