Discussions about moisture buildup and its effects are likely to be among the most enduring conversations in homebuilding and remodeling, particularly as more homeowners opt for better-insulated and more-airtight exterior walls.In his Musings of an Energy Nerd column, GBA Advisor Martin Holladay recently sorted through key considerations for designing exterior walls that manage water condensation and perform well when exposed to cold weather. The variables in Martin’s analysis include the indoor relative humidity and the temperature of a wall component, such as the sheathing. If the sheathing gets cold enough and the indoor relative humidity is high enough, condensation can collect on the sheathing.The condensation issue came to mind again this month when we spotted an Alaska Daily News story (sign-in required) about mold problems in houses in Fairbanks, where home energy conservation has been gaining importance since the 1970s, when fuel costs began to rise. The stimulus-funded expansion of the Weatherization Assistance Program and recent home-energy rebates have further advanced weatherization activity in the area.The ventilation issueBut as more homeowners add insulation to attics and exterior walls, and air-seal the shell as best they can, complaints about mold have grown commensurately. A building inspector and retired energy auditor interviewed for the story noted that the design of the exterior-wall systems in the afflicted homes plays the most prominent role in mold growth, related health issues, and structural damage precipitated by long-term condensation problems.Because these are existing buildings whose exterior walls are unlikely to be redesigned and rebuilt, however, homeowners are advised to examine a factor they can address more inexpensively: ventilation.“People are still too often addressing one side of the energy equation … making walls thicker, increasing R-values and tightening homes. They are not addressing ventilation,” Steve Shuttleworth, a building official for the city of Fairbanks, told the paper.As noted in another Musings of an Energy Nerd column, “Designing a Good Ventilation System,” builders nowadays typically choose from among three mechanical ventilation systems: an exhaust-only ventilation system based on one or more bath exhaust fans (this is the simplest system); a central-fan-integrated supply ventilation system (for better fresh air distribution); a heat-recovery ventilator or an energy-recovery ventilator connected to a dedicated duct system (the system that will operate at the lowest cost).The choice depends on factors such as the size, layout of the house, and the budget of the homeowner. Martin’s column provides a thorough description of the options.
Costs In 1956, solar panels cost about $300 per watt. The 7.5 kW system could only be afforded by the very rich.Today, prices have fallen significantly. In most areas, solar panels operate at around $3-5 per watt. You will pay closer to $3 if you install it yourself, and closer to $5 if you have professionals to do so. For 7.5-kW or 7500 watts panels, you could pay from $22,500 to $37,500.If you need less electricity, of course, the number gets lower. If you only consume 600 kWh per month or 20 kWh per day, you could install a system with a capacity of up to 5 kW which would cost around $15,000.Of course, you could partially supply the house with solar energy. If you want to invest $10,000 in solar panels, you can add electricity from the grid with a 1.5-kW solar system.However, tens of thousands of dollars for solar panels are still quite exorbitant, especially since it can take decades before the money is redeemed.You can rent them (the panels), though. There are no advance payments. Homeowners pay a monthly rent for the use, and the rental company owns and supports them. Over the past 10 years, rooftop houses with solar panels have evolved from curiosity to a common phenomenon. This technology has been available for decades – astronauts have been using solar-powered satellites since 1960, and in the Second World War, passive solar heating systems, which convert solar energy into heat instead of electricity, have been used in U.S. homes.However, the introduction of active solar systems as a consumer good turned out to be an issue. Active solar energy uses photovoltaic panels to convert sunlight into electricity, and this has traditionally been a prohibitively expensive technology.The advantages of solar-powered residential buildings are obvious: solar energy is infinite (at least for the next 5 billion years approximately), provides clean energy without emitting greenhouse gases, that may save people’s money on their electricity bills.But there are factors to consider when deciding on solar energy – and the cost is just one of them.In this article, I will consider 6 of the most important issues that need to be addressed when you think about investing in solar panel installation. The use of photovoltaic energy is a very “green” solution and a potentially useful step, but it is not as easy as getting energy from a conventional power grid.Solar Panels Installation. The first factor is the one that you, perhaps, weren’t even considering: Thanks to The Home Dweller for Image. Roy Emmerson Contrary to what most people think, the size of a solar power plant has nothing to do with the size of a house. Instead, only 2 parameters should be considered:insolation which we have just discussed;the amount of energy you need.To get a very rough estimate of how big the system you need should be, look at your electricity bill and find out how much kWh you use per day.The average house uses around 900 kWh per month or around 30 kWh per day. Multiply this by 0.25 and get 7.5, so we need a 7.5 kW system.A typical solar panel produces up to 120 watts or 0.12 kW per day. To provide 7.5-kW, you need about 62 panels. One panel can be about 142 x 64 cm, so that the 62 panels will occupy about 65 square meters.You should also consider the insolation and how many hours of sunshine peak-hours you get per day, make adjustments if you use rechargeable batteries with the panels as well. Therefore, it is best to contact a professional. Turning your home into a solar energy station requires more than using a conventional old power grid. But not much.Solar panels have no moving parts. They are a part of a complete stationary system. So, once they are installed, there aren’t many things that can go wrong. Almost the only one a house owner should do is to keep the panels clean. That’s important because too much snow, dust and bird droppings on the panels can reduce the amount of sunlight. Dust accumulation on the screen can reduce the amount of electricity produced by the system by as much as 7 %.There’s no need to do this once a week, though. It is sufficient to water the panels with a hose once to four times a year. You don’t have to climb on the roof to do this. The hose with a nozzle works perfectly from the ground. If there is construction work in your area, you need to clean the panels more often to avoid additional dust accumulation of building debris.Also, periodically check that all parts are in working order. You need to replace the batteries as well, but this is once a decade. Tags:#solar#solar energy Roy Emerson is a technology enthusiast, a loving father of twins, a programmer in a custom software company, editor in chief of TheHomeDweller blog, greedy reader, and a gardener. Sunlight is obviously the key when it comes to solar energy, and not all regions have equal conditions in this regard. It is important to know how much sunlight reaches the ground in the area where your potential solar home is located.What we are talking about here is called “insolation”, a measure of how much solar emission will fall to the ground in a given area over a given period of time. This is usually measured in kWh / m2 / days and it will show you how much sunlight will be available for your solar panels to turn into electricity. The higher the insolation value in your region, the more electricity each of your panels will be able to generate. A high insolation value means that you can get more energy from smaller panels. A low value means that you might end up spending more to achieve the same output power.So you have to build your solar home in the southwest, not the northwest? Far from it. This simply means that you will probably need more panels to achieve the same output power. Coverage Related Posts Maintenance Surroundings Insolation Recycling The location of your house has a great impact on your solar energy efficiency. It’s an obvious problem – if your electrical power depends on sunlight, things like tall tree shadows and high building shadows will be a drawback.This is an even bigger issue than some people realize. Different types of panels differently react to shadows. While polycrystalline panels can significantly reduce the output of electricity, any part of shading on a mono-crystalline panel will stop electricity production completely.Thus, to build a solar-powered house, it is necessary to make sure that there is no shade on the roof panel during sunshine hours per day (usually from 10 a.m. to 2 p.m.) and preferably during all solar hours. The more hours the panels are exposed to full sunlight, the more efficient the production of electricity will be.Achieving the greatest efficiency can mean trimming or completely removing trees on your site. If your home is surrounded by high-rise buildings that block the sun, you should pull them down too 🙂 If you can’t do that then that’s a big problem. Aramco, Holder of the Largest IPO in History is… How Battery Storage Is Revolutionizing the Sola… The Top 5 Issues Faced by Futurists Get Smarter About Enterprise Management with AI The service life of solar panels is 40-50 years, the controller and inverter – 15-20, batteries (depending on their type and usage) – 4-10 years.Although the issue of disposal of solar panels remains open, only 30% of all manufacturers take them back for recycling. But nevertheless, the demand for spent solar panels is growing every year. As extraction of rare metals becomes more and more expensive, and processing of the panels will lead to their reuse.In addition, there is a secondary market for photovoltaic and wind-electric sets, where already used equipment can be further used. In countries in transition, former solar modules can be used. Due to the more intense solar emissions, these modules can produce more electricity. An example of this is the second solo project – an online platform for the purchase and sale of used modules.
Kanimozhi at the Patiala House court for the 2G trial in MayLodged in the assistant superintendent’s office in Tihar Jail in a cell especially created for her because of security reasons, Kanimozhi misses her 10-year-old son Adithyan the most. He is under the care of his grandmother Rajathi Ammal. She,Kanimozhi at the Patiala House court for the 2G trial in MayLodged in the assistant superintendent’s office in Tihar Jail in a cell especially created for her because of security reasons, Kanimozhi misses her 10-year-old son Adithyan the most. He is under the care of his grandmother Rajathi Ammal. She also misses her diamond nose-pin, an accessory she has sported since she was a little girl. She had sought permission to continue wearing it, saying she felt “improperly dressed” without it, but jail authorities did not allow it, or indeed any other jewellery.Adithyan visits her often, but not often enough, as jail rules allow visits by family members twice a week. That is the only time her calm cracks. “Once she broke down and kept saying sorry to her son”, disclosed a jail official who understands Tamil. Though the prisoners meet their families in ‘mulaqaat’ (meeting hall) with a glass shield in between, she was allowed to meet her son in the superintendent’s office because she wanted to hug him.Jail officials say Kanimozhi keeps to herself and does not interact much with other inmates. By various accounts, she appears to be an Orhan Pamuk fan. On May 20, when she was sent to jail, she carried a half-read My Name is Red with her. Museum of Innocence by the same author is keeping her company now. Kanimozhi spends her time reading and writing poetry. “She keeps writing something or the other and is completely immersed in it”, reveals a jail official. She was earlier lodged in ward number 8, which is called the ‘mulayaza’. It is a place where new inmates are lodged for the first six months to prevent them from interacting with the more hardened inmates. It is the only ward which has a spacious courtyard in the centre, where inmates can mingle with each other.advertisement”She is the calmest of the 2G lot and doesn’t make unreasonable demands”, says the jail official, referring to the other vvips lodged in Tihar for the 2G spectrum scam. They include former telecom minister and Kanimozhi’s party colleague A. Raja, the Balwa brothers, Unitech’s Sanjay Chandra, Karim Morani, Kalaignar tv’s managing director Sharath Kumar, senior bureaucrats and corporate executives.Till June 10, it was not very difficult for her or for the others in the 2G case to spend the day since they had daily hearings at Patiala House. They were out of the prison at 9 a.m. and returned around 6 in the evening. The day was spent in the air-conditioned CBI court, where the accused could meet their families. Now, with the courts closed for vacation till June 24, the day has to be spent in the jail.A jail official said that she once enquired about a beauty parlour on the premises. “She was told about one run by jail inmates which is free of cost, and the other run by Jawed Habib which costs money. She has not visited either yet”, the official said