Is sleeping in daytime a hindrance to accumulation of spiritual energy?
Sleeping during the daytime need not be a hindrance to our spiritual awakening. Of course, it depends on the reason for sleeping in the daytime! If one also sleeps at night, then too much sleep is to be avoided. As Krishna states in the Bhagavad Gita: yoga is not for one who sleeps too much or sleeps too little!
If one meditates by night and sleeps by day, this is, of course, a different question. But you haven’t put the question in this way. A rule of thumb (only very general) is that 7 hours of sleep should be sufficient for most people on a regular basis. Age, whether very young or very old, can require more sleep. One’s mental condition or degree of discomfort due to arthritis or other conditions generating pain might require more sleep or prevent adequate sleep.
But as your question is not about the number of hours of sleep, let me say that sleeping in the daytime is not by itself, a hindrance. More important than this is the depth of meditation and prayer; the purity of one’s actions (selfless service, nishkam karma, action as devotion, etc.), and purity of one’s heart. God doesn’t mind our shortcomings but seeks only our love and devotion.
“Blessed are the pure of heart, for they shall see God!” Wakefulness IS important and yet the health of body and mind are great aids to Self-realization and wakefulness. One who goes without adequate sleep falls too easily into subconsciousness (as does one who sleeps TOO much!).
What is right for one is not helpful for another. DO WHAT WORKS for you. Do what allows your mind to be clear; your heart to be pure; your actions to be dharmic.
Blessings and joy to you!
Seattle WA USA